Do the Past and Future Exist?

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Is all that exists just whatever exists right now? Is the past erased and the future a void yet to be filled? Well, the answer lies in between the past and the future - in the elusive, ever-moving eye-blink that we call the present.
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Hosted by Matt O'Dowd
Written by Matt O'Dowd
Graphics by Leonardo Scholzer, Yago Ballarini, & Pedro Osinski
Directed by: Andrew Kornhaber
Camera Operator: Setare Gholipour
Executive Producers: Eric Brown & Andrew Kornhaber
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Runtime: 16:05

Comments

ja v
ja v - 52 minutes ago
When we remember something is it happening somewhere else?
Christopher Johnson
Christopher Johnson - Hour ago
Sounds like there is a god
Adam Ant
Adam Ant - 2 hours ago
Time and space flow through us!
Adam Ant
Adam Ant - 2 hours ago
No past no future we are the infinity
Quetzel Coatl
Quetzel Coatl - 3 hours ago
🤣
Quetzel Coatl
Quetzel Coatl - 3 hours ago
You better have Jesus Christ
Zephiroth Stryfe07
Zephiroth Stryfe07 - 4 hours ago
So this video(4 me) WAS made in the past, while i'm writing all this words and letters are becoming the past too(scratch my nose), is also on my past now. BUT people in the future will read this(i think). Also, we live in The Lego's Universe now?. Nothing in the Universe is a Line, a Square a Brick or a Block, not even Clocks, real ones i mean not digitals. So how can i believe anything this dude says, said or will say, when you try to explain Time and Universe with Blocks, Lines, Dashes and Dots?
islandonlinenews
islandonlinenews - 4 hours ago
The present isn’t a moment it’s an eternity.
Gerard Ahern
Gerard Ahern - 4 hours ago
These are the same consepts as the bible codes.
Nikki Staxx
Nikki Staxx - 5 hours ago
Welp, I’m gonna have to watch this video a second time.
Hexi
Hexi - 7 hours ago
No, because time does not exist. It's simply a unit of measurement to measure the rate of movement.
Richard Garcia
Richard Garcia - 9 hours ago
Also! “I think, therefore I am.” Why is that everyone’s go to for philosophical enlightenment? I’m tired of hearing it because it’s non-sensical and only reinforces the unsophisticated ideology that you are anything other then your thoughts. You don’t think! “YOU” CANT DO ANYTHING BECAUSE “YOU” DON’T EXIST! At least “you” don’t exist as anything other then everything else. It’s so simple and elegant, how is this not conceivable to people?
Richard Garcia
Richard Garcia - 9 hours ago
Both ideologies about the “universe” being a stupid mechanism or being created are very wrong.
Jack B
Jack B - 9 hours ago
No, and neither do Birds.
Get over it.
Richard Garcia
Richard Garcia - 9 hours ago
With our Right hand we fight to understand and rationalize our existence but with our left hand we sabotage our ability to be aware of it. We humans have a sort of natural psychosis about ourselves.
Richard Garcia
Richard Garcia - 9 hours ago
For all of the religious people, I’ll explain it this way. God is so bored of being God, God spends all of eternity pretending not to be God.
Richard Garcia
Richard Garcia - 10 hours ago
As hard as it may be for you to accept, there is no Universe outside yourself. It’s inside you and you’re inside it. We exist like a Klein Bottle in relation to everything “else outside you.” In reality you can only say what you’re not, you can never really say what you are. There are many common sense ideas that give away the show, the only reason you can’t understand is insecurity. Fear, power, motive, desire, it can all be chocked up to; we really don’t want to know because ignorance is bliss.
drewbert83
drewbert83 - 10 hours ago
Think of alpha centauri. We observe it as it was 4 years ago. Things have happened there that we have no way of knowing. And so if the future already exists for alpha centauri, then it must also already exist for us. Eternalism confirmed.
Let’s take a walk
Let’s take a walk - 10 hours ago
Past and future exist, but the present does not.
Wally Wally
Wally Wally - 11 hours ago
Only a prediction exists in this matter. Not accurate information.
dutchrjen
dutchrjen - 11 hours ago
"Now slices" are irrelevant. They do not say anything about the universe because we can ONLY see "now" in a single location.
"Now slices" are just perception we have as a limited observer. We can map the entire universe onto a single preferred foliation perhaps that's the true "now." All except this one foliation could merely be perception. The universe could be a block or perhaps something else explains it.
As an observer we are limited in what we have the ability to know.
Sylak
Sylak - 12 hours ago
I'm more in the presentism view. Althought as a none physicist, my opinon on this is useless :-). But to me, if you wanted ( in your slice of universe/time) travel to the past, you will have to reconstruct every single, smallest unit of reality to the quantum states there where in at the moment you wish to travel. Because it doesn't exist anymore. and since the furtur doesn't exist, you can't go to it, you could "build" it maybe. but changing every quantum states of a whole universe seem crazy. Since we know that GR and space/time are incomplete, I don,t think the whole worm hole to the past, exist. well not to the past of your slice/box of time, maybe to a difference point in time of a places where time flow slower of faster than your own "box". that exist at the same time as your present.
all probably wrong, but I like the thought exercise, and whatever become real, I'll accept it from my physicist overlords.
ak11230
ak11230 - 12 hours ago
I did study about space and time is like V letter at some point space and time become unity .
Nothing move expend no time ... Time stops....
After years of looking into times and space ? I know I don't know nothing .....Ak
ValenHawk
ValenHawk - 12 hours ago
Would Entropy be the equivalent of the motor in the phonograph ?
Ronald V Ronca
Ronald V Ronca - 13 hours ago
More nonsense from the scientific community to further impress upon the laymen their superior intellect. Listen to this man, he is explaining a possibility while trying to sound profound....there are theories upon theories constantly being presented....it's all possibilities, probabilities, theory and guesses. Only in time will we find the answers....but then what if time doesn't exist, in that case why bother, without time there is nothing.
George Clinton
George Clinton - 13 hours ago
Do I understand correctly, that the present is the same to everyone, but the delay between the real present and our perception (which is to get the light travel to us from an event) causes that we don't agree on what's happened when?
Or I didn't understand anything about this video?
Jesus Guevara
Jesus Guevara - 13 hours ago
Hey you guys are idiots time doesn't exist, time is just a concept that humans created in order measure how long something last. No other existence in the universe uses the measurement called time except humans.
Aaren Cordova
Aaren Cordova - 13 hours ago
Can't say how much I love this channel enough!
Jesse
Jesse - 13 hours ago
The light cone arguments are comprehensible enough and it's relatively clear how they change each observer's *perception* of the universe, but they don't really eliminate the concept of the present - they just make it impossible to calculate as any observer constrained by light-speed. But as we can see in *all* the depictions, an observer unconstrained by light-speed can define the present quite easily - a discrete t-axis is still present, it's just not accessible to the inhabitants of the block universe as their own perceptions of time are indelibly altered by position and velocity within the block.
One key indicator of something akin to a 'true present' is that there is never a possible light cone that lets me see another observer's future *before they do* . I can see other elements that will interact with them in the future before they perceive them, but I can NEVER see another observer's future - or my own - I can only see nearer or further into their past depending on our relative positions and velocities. Even the super-luminal traveler can't see *my* future - they can only travel into the image of my distant past and back.
This absolute bulwark protecting the Future from exploration strongly suggests that there *is* a present, even if it's hard or impossible for those of us experiencing it to agree on exactly what it is.
David Barber
David Barber - 14 hours ago
Cultures think of time differently, unfortunately since colonizers control the world by force we generally think of time in the way THEY think of time ie Roman Thought
Sulanis
Sulanis - 14 hours ago
So Here's a question for you? Based on this Cone of light that we observe. Is it possible to Take a Satellite and put it at the 4 corners of the solar system and extend of Cone of Light? I know it would still take a long time to reach us at earth again, but its like taking a sneak peek?
S -------------------------------> E
Raw Engineer
Raw Engineer - 14 hours ago
"But interpreted some ways" - i.e. made up for the benefit of sci-fi writers because that's all physics is for these days.
Tim Robb
Tim Robb - 15 hours ago
9:12 Instructions Unclear, stubbed my toe and caused a Big Bang. Sorry guys
Cid Sapient
Cid Sapient - 15 hours ago
lol every time someone talks about determinism and perception of time all i can think about is the one electron universe theory
Mark Pressley
Mark Pressley - 15 hours ago
The present is the superposition of the past and the future! :-)
GeoDen
GeoDen - 17 hours ago
The past HAS existed, the future WILL exist. However you look at it.
Mr. Orc
Mr. Orc - 17 hours ago
Not a perfect accent for all type of people to understand.
last name first name
last name first name - 17 hours ago
My Ears hurt and my head hurts, I have 2 ouchees!
Green Nights
Green Nights - 17 hours ago
So Much Universe, So Little Time. The current crisis in cosmology and how we got here.
https://www.youtube.com/watch?v=0sfvQ_fsil4
we got here relying on time, which only leads to more questions and dead ends.
tehdreamer
tehdreamer - 18 hours ago
Jonas from Dark is now doing physics youtube channel
Hector Ganzon
Hector Ganzon - 19 hours ago
he got thin.
mark mac
mark mac - 19 hours ago
Yes it does because the now would never be.
Natas Diablo
Natas Diablo - 21 hour ago
Jaykee the Wolf: past, present, future do not exist.
Luis: ??
Jaykee the Wolf: Without consciousness.
Luis: genius. you deserve a beer for that one!
Fabien Vidal
Fabien Vidal - 22 hours ago
There is something wich I find unconvincing in the definition of the present being your light cone.
Would "simultaneity" be restored, if the definition of the present was "the state of every object in the universe when the time taken by light to reach your present position equals light speed / distance" ?
agc
agc - 21 hour ago
The problem with this, I would assume, is the term "distance." The distance between your present position and every other object in the universe, is constantly changing with time. So in order to judge your "now" with every other "now", you would need to take into account many future and past moments too that are crucial factors in just how long it takes light to reach you from those "nows." So in that sense, you can't talk about "simultaneity" and "now" in a vacuum, because to do so, you need to speak in terms of hypothetical light rays to traversing distances that are fluctuating and affected by NON-simultaneous events. If the measurement of your simultaneous event is dependent upon events that are non-simultaneous, I think that raises a huge problem. Basically the fact that light is not instantaneous, rules out the possibility of a single "now" in the universal sense. Perhaps you could define a logically consistent convoluted definition of "now", but from a universal perspective and physical perspective, it would have no actual meaning in reality.
Michael Pierce
Michael Pierce - 23 hours ago
I think it's important you include an argument that block time exists rather than it being based on a imaginative experience. You can imagine the structure in some sequence of events as happening at once like some over exposed film, but that isn't an argument for it actually existing as a physical trait of the universe, other than the firing of neurons that constructed the image in your mind.
Even the argument of a position being an electron traveling backwards in time was a mathematical assumption in Feynman's style of simplifying the universe in order to get answers at the scales he can work with and observe.
Kristian Larson
Kristian Larson - Day ago
How do we know that time is a different type of dimension and not just a higher dimension that we happen to perceive differently that the other three?
Also, if two objects move directly away from each other, each moving at 75% the speed of light, would one not appear to move at 125% the speed of light relative to the other? Or am I not understanding the funky physics correctly?
agc
agc - 22 hours ago
I don't know what you mean by "higher dimension." It certainly is another dimension. You can also do geometry with time as a dimension. But here's the interesting thing that distinguishes time from space. Take a piece of graph paper. If you plot 2 co-ordinates on the graph, and draw a straight line path between those two co-ordinates of SPACE on that graph, that straight line path would correspond to the shortest distance possible between those two points. But now imagine your graphpaper is made of spacetime. If you plot a straight path between two co-ordinates in SPACETIME, that straight path, is still the shortest spatial distance, but it also is the LONGEST TIME DURATION possible too. So the FASTER you reach another point in space, the SLOWER you reach another point in time. And this has a lot to do with the speed of light / relativity and why light has a universal speed limit. And it addresses your second point. No, the 75%s don't add up in that way. The faster something is moving away from you (distance-wise), the slower its clock appears to tick. It's built into the fundamental geometry of the universe that it will balance out. The quicker you go through space, the slower you go through time, and vice versa. Nothing can travel faster than the speed of light.
V 4 Vendetta
V 4 Vendetta - Day ago
I believe that there is no such thing as time. Only our perception of time based on change
Simon Sozzi
Simon Sozzi - Day ago
Didn't you already do this video?
vbddfy euuyt
vbddfy euuyt - Day ago
When you live in the past, you are depressed; when you live in the future, you are anxious.
JSyntax
JSyntax - Day ago
I have one word for you ... tenet
Matt H
Matt H - Day ago
Wut...
River Chicken
River Chicken - Day ago
Next big miss is the concept of entropy. Once again life ruins it. Also, they have the concept backwards. The natural state of energy is to be as spread out and broken down as possible. As things decay, expend, radiate, dissipate and move eventually towards an even distribution of heat energy (aka the end of the Universe), it moves towards order - not away. A perfectly even distribution of energy would be "perfect order". A chunk of mass is disorder, the end of the Universe is perfect order. The universe moves away from disorder.
vbddfy euuyt
vbddfy euuyt - Day ago
said enough about this for now, but i will leave you with one last thought. Consider that it is all about consciousness and many worlds and - REALITY=INFINITY/ZERO
River Chicken
River Chicken - Day ago
Physics doesn't work when run backwards. That apple wouldn't fuse back together if the events were simply run backwards. Some things work, but all do not. Big miss by contemporary physics to still be claiming this.
River Chicken
River Chicken - Day ago
@Carlos Grant correct, which is nonsensical here in reality. I have heard it all to date. The same folks say it is impossible to know the location and velocity of those particles, which would be required to complete that operation. I am going on what the physicists are saying as well, and I love that we're all having fun trying to get to the answers. I also know that sometimes all they have to extrapolate with is math. Math does not always predict reality however, and is important to keep in mind when considering the "If".
Carlos Grant
Carlos Grant - Day ago
Sorry, another forgot: Nobody in the video is claiming the apple would be "unsliced". That diagram is just to show what a now slice is in a block universe and how two observers in different frames of references will not agree in what now is.
Carlos Grant
Carlos Grant - Day ago
@River Chicken Sorry, I forgot to mention that I wasn't talking about rewinding time. It's not possible to do that...
Carlos Grant
Carlos Grant - Day ago
@River Chicken Here's the answer: By the law of physics the apple would, yes, fuse back together. This was demonstrated before but using a glass breaking and fusing back together. Apparently (as in, I'm not the one saying this) If you knew where every atom of that apple was and if you could somehow reverse the trajectory of every atom in that apple after it was sliced, if you could simply push it back with the same exactly force that slit it but in the opposite direction then the apple would come back to it's original state and what would not break any law of physics. Again, this is not me saying... I know about entropy and how hard is to unscramble an egg but they say if you could manipulate it at an atomic level it would't break any law.
River Chicken
River Chicken - Day ago
@Carlos Grant They do, it is accepted as being true. I ask you, how exactly would that apple come back together as if it were unbroken? I agree all of the "movement" physics work when it is breaking apart, but the apple would not "fuse" back together under any circumstances by reversing the flow of time. In other words, that event if time were reversed, would be impossible in the current Physics model.
River Chicken
River Chicken - Day ago
Everything about the Universe seems deterministic, except the free will of life.
Green Nights
Green Nights - Day ago
Paradigm shift - future is written, and creates the present; or you would not exist in this paradigm if you had no future. If the past created my present I'd be dead already; read my bio and see what never happened to me in the past, according to the future.
For the fun of it
For the fun of it - Day ago
past will always exist...future! no one knows
Al Garnier
Al Garnier - Day ago
The present is a Planck second of time in material existence. The past is recorded in the fossil evidence and electromagnetic output of the electrons work product in electromagnetic waves.
The future is predictible but, only if you are fully aware and in the present about the past and the likelyhood of the future events.
We live in the past and stuggle to remain in the moment.
Al Garnier
Al Garnier - 12 hours ago
@Green Nights Logic is material evolution. My logic is based solely on scientific, material evidence. I trust nothing without empirical evidence. My logic is based on the scientific evidence of electron interactions in the causality of evolution. You are trying to validate your limited ignorance as evolutionary logic without a shred of evidence to support the ignorance. It is your ignorant beliefs without science that is the illusion of your delusion. The fundamental electron and its unique spin/charge characteristics is the answer to the the causation of our existence.
Al Garnier
Al Garnier - 14 hours ago
@Green Nights Logic is reality. Genius does not exist in consciousness. Knowledge exists in the evolution of materialism and consciousness, without knowledge of material events, is a wasted life in emotional ignorance. Genius emerges from the sharing of empirical knowledge and the evolution of materialism. The genius is, to influence the future of material evolution through conscious intervention.
Al Garnier
Al Garnier - 17 hours ago
@Green Nights Logic is the manifestation of material evolution through the mathematical processes of harmonic wavefunctions and resonances and is recorded in time and engrained in materialism as fossil and electromagnetic entropy. We unwittingly exist in the present and live in the past, trying desperately to understand our future. We are idiots trying to comprehend materialism from ignorance. Our stupidity is our belief in fear and emotional ignorance instead of searching for truth in material evolution. The present is evolving but, the past still exists and is irreversable but, whatever may come in the future is dependant on the next note in the symphony. It's either harmonic bliss or, abstract disharmony and survival of the symphony is dependent on your logical choice and natural selection. Make the wrong choice and your future harmony is jeopardized.
Al Garnier
Al Garnier - 18 hours ago
@Green Nights Time is real and reality is timeless. It's actully you who are the illusion from the first memory of your big bang birth until the day you die. Consciousness isn't fundamental, it is emergent from biological evolution and we're just lucky enough to be one of the chosen few to experience it without having to believe in anything except our experiences. Reality is what it is, we just have to be conscious enough to understand and control our enviornments. We are developing Artificial intelligence to better understand the logic of reality, it is too technical for human emotion to grasp the mathematical intricacies of the Big Bang's harmonic resonances.
Al Garnier
Al Garnier - Day ago
@Green Nights Right, and the Twilight Zone is where you'll wind up if your not fully cognizant of the past! 😉
holylingus
holylingus - Day ago
Meaningless in the absence of time. What never was is never again.
Arnold Barzydlo
Arnold Barzydlo - Day ago
I actually wrote a research paper on this about 40 years ago. Andrei Linde of Stanford lifted my space-time maps from the paper and took them out of context, now there are posters of them in physics departments around the world showing maps of the expanding universe with one crucial omission... my maps showed the dividing line between past and future. The present is an impulse wave coming from the primordial singularity, a sharp pulse of energy being introduced into the universe at the beginning of space and time. Energy must be conserved, so the impulse wave propagates from past to future, altering the geometry of space-time as it goes to incorporate the new energy into the manifold. On this sharp dividing line between past and future change must occur. This is the phenomenon of the present, and it is a repetitive phenomenon. It is known as the energy of action, it appears in all our equations as the Planck constant. So, yes, the past and future do exist, but in a static state, and every impulse wave of energy introduced through the primordial singularity re-initiates physical reality, re-plays our history, but each impulse wave provides fresh energy to make subtle changes to the history of the universe. The "many worlds" interpretation of quantum physics is wrong. Every object in the universe has a book of histories to choose from for actualization, the number of pages depending on how many impulse waves have been introduced thus far, and the universe of objects is better viewed as a vast library filled with such books. When the quantum wave function collapses for an object, it is nature finding a compatible history for the object in that object's book, and actualizing it. If there are no compatible histories for that particular object, the universe uses some of the energy of the impulse wave to write a new page in the book of that object's potential histories. If nature actualizes a previous history, it need only annotate the page that was used. Even "Base Reality" is a simulation, computing cycles have to be minimized to keep reality from bogging down the cosmic processor. That's why quantum physics is so weird. There's no point in selecting a history for an object until it matters, so things are left indeterminate until something interacts with the objects and forces nature to select a history for them to actualize. I've explained this many times over the last four decades, but your physicists are more interested in piracy to profit their personal careers than they are in finding answers or knowing the truth of things.
Arnold Barzydlo
Arnold Barzydlo - 11 hours ago
@Carlos Grant You kind of lost me on the alien in another galaxy thing. Let me see if I can give you a simpler analogy of how this works. Think of the history of the universe as a movie film. The projector of the movie can only illuminate one frame at a time. The movie is a recording, so once you're done watching it, you can load it back into the projector and watch it again. The thing about this movie projector though is that it's magic, every time it shines the light on a frame in the movie, it very subtly changes the image, adds a bit more detail, or even re-writes a scene. So, every time you load the movie into the projector, you notice the movie has changed a little bit from what you remember. The entire history of the universe is laid out in the time-like dimension, but when we introduce a sharp pulse of energy into it at the beginning of space and time, we've reloaded the movie and that pulse of energy will go through it frame by frame both replaying it and changing each frame a little bit based on what is already recorded there. Does that clarify it any?
Carlos Grant
Carlos Grant - Day ago
Although it was hard to follow your explanation, the parts I understood I liked it, so thanks for posting that. I just don't understand something about this notion that the future already exist. So, if for example my present or my "now slice" may contain the future of an alien in another galaxy... how can that be?
Q WWG1WGA
Q WWG1WGA - Day ago
WTH?
jomen112
jomen112 - Day ago
Isn't the impression of the existence of different "slices" of the present only an artifact of ignoring the fact times run different for different observers? I.e. if you take different clock speeds into account would that not imply that everyone shares the same "slice" of the present? At least that is how I understand it, but maybe I got it wrong and if so what do I miss?
Carlos Grant
Carlos Grant - Day ago
This concept (Relativity of Simultaneity) only works when you think of what two (or more) observers consider to be happening right now in the universe. Only two people stationary to each other will share the same now slice. You and an alien in another galaxy would agree on the same "now slice" if you were somehow both stationary to each other. But, let's say that alien hops on a bike and starts moving towards you. Now his present will be aligned with what you considers the distant past. if the alien turns around and start riding his bike away from you then his now slice will cut at an angle and what he considers as happening right now in the universe will include your distant future. I'm quoting a video from Brian Greene on youtube. You can search for brian greene now slice. That is a "dumbed" down version of what this PBS video talks about.
Harold Beaumonth
Harold Beaumonth - Day ago
All life on earth has eggs to produce another form , the only living creatures that laid eggs where the dinosaurs, a comet wiped out but left the eggs to preserve in the ice.
trutheory algorithms
Wow. This video was filmed and edited , a past existed, proven.
We, are now & present. Oldest recorded human is around 160 or less so a personally relativistic concept of 'now' could be the length of a 'life's' span.
If you eat food you KNOW there is a future.
This whole video uses Perspective as it's proof of concept. As soon as you started plotting points on a graph and then talking about a separate past for a second set of points you just restated general relativity . when you ask about existing simultaneously, no. Just because there is no observer doesn't mean there wasn't something to be observed. But there is a now and there is a finite past and there is an infinite future.
riana mohamed
riana mohamed - Day ago
Thanks. Totally confused now.
Anurag Gupta
Anurag Gupta - Day ago
Hi sir. You are requested to make a video on this:
1. When does the sun's magnetic polarity get reversed?
2. What impact will it have on the Earth?
3. Recently in 2020, the sun's polarity has been reversed, for the 25th cycle. When was the first cycle occurred?
4. Approximately when will the 48th (final) cycle occur?
5. What will happen, when the final 48th cycke occurs?
6. Whenever the first cycle had occurred, before that had no polarity reversal cycle ever occured on the sun?
7. Will the sun never ever change its polarity, after the 48th (final) cycle?
8. If the answer to question 7 is that the polarity will stilll be changed even after that, then why is the 48th cycle considered as the final cycle?
9. If after the 48th cycle, any new fresh cycle starts, then what will be different in the cycle? Why will be a fresh new cycle and not the 49th cycle?
Larry Lee Lethbridge
you cant go into the future unless you go back in time first because its not written I mean recorded yet.
Michael Bartlett
Michael Bartlett - Day ago
Einstein was a very intelligent person and he contributed a lot to our knowledge of light, speed, eluded to mass, energy and relativity, but as an intellect and thinker, he is not qualified to hold Newton's crotch protector! Newton was and IS right about the universal clock and nothing exists other than the present instant in the ticking of the cosmic clock.
As you so aptly demonstrated in your video, every action that is taking place in this instant is happening regardless of it's position in the universe, but requires an observer to make it a part of our perceived reality. Countless supernova explosions are happening in this instant throughout the known universe, and even though they are not visible to us, they are happening at this moment.
The past is behind this moment, and the future is yet to be written and is certainly not determined. Yes, any movement or displacement of a conscious observer changes their perception of reality, but not what happened in that tick of the cosmic clock, but space, time and speed will alter different observers perceptions of it. It would matter not if you could travel at warp speeds, 10, 100 or 1000 times the speed of light, you can never go backwards in time with respect to Newton's cosmic clock.
The question of determinism can not be separated from the debate over consciousness, which I will address here later. But, that being said you should also know that I have subscribed to the multiple-worlds theory for many years now, and it is based on the relationship of perceived reality to consciousness.
Some amount of determinism does exit on the macro-level,and plays out under Newton's cosmic clock. Think about it like the impending merging of the Milky Way with Andromeda and other Newtonian physics down to and including our solar system's existence and our sun's interactions with other stars in our galaxy.
However, determinism on the micro-level as it relates to our lives is much less a factor. Consciousness plays a much bigger role there. Peoples lives and events that occur in them are determined more by our conscious decisions that are made in basically three different ways. Many are made emotionally, while some are made logically, and some are a combination of both.
The timelines of our lives generally follow the path that we lay out for our lives from the time we become sentient until the time that we appear to die to others around us. If you want to see the difference that your conscious decisions make on your reality timeline try this experiment.
Make a conscious choice to let any significant decisions you make for a set amount of time be determined by a coin toss, a purely random act of chance. I assure you that the events of your life's expected time line will change drastically, but it will fit nicely with the many worlds theory.
Now, lets talk a little bit about consciousness and it's effect in our lives First, without consciousness there is nothing, and I do mean NOTHING. Our perception of reality actually creates reality. Without our ability to perceive it, it would not exist. Without consciousness everything that existed would be totally predetermined, but there would be nothing to acknowledge it and give it substance - No reality could exist.
Consciousness is in fact a very complex electromagnetic waveform generated by all sentient life forms and just like in electronics theory, the product of merging of all those complex waveforms results in more waveforms that are the sum, the difference and the two originals. The number and types of those interactions are innumerable, or if you prefer "infinite" , although I dislike using that word because infinity does not exist any more than "zero" exists in our reality and math.
You are the Captain of your own ship of destiny and you pick the ports. Your own reality IS what your mind and senses perceive it to be and it is just as real and valid as anyone else's perceptions of it.
If you only consider the nearly eight billion people on this earth with which we have a somewhat shared perception of reality, less with some and much more with friends, family and colleagues, you should quickly realize that it can be considered to be a giant venn diagram with intersections indicating the areas where our perceptions converge into a shared reality.
If you are reading this, our venn diagrams are converging and there is a sharing of our perceived reality going on right now.
I have said enough about this for now, but i will leave you with one last thought.
Consider that it is all about consciousness and many worlds and - REALITY=INFINITY/ZERO
Larry Lee Lethbridge
Time exsists so that it can be recorded on the God.My liveing universal Matrix
KmuffsFPV
KmuffsFPV - Day ago
Could it be true that time is not a requirement to describe the "present" and therefore your discussion about light cones doesn't apply. Imagine instantaneously freezing the whole universe (not just the observable universe) at any given moment. Different observers might disagree about when the universe was frozen but surely such a slice of the universe is conceptually valid? Maybe time is the illusion and the only thing that exists is present.
agc
agc - 19 hours ago
Basically, what I'm trying to say, is that your request of "imagine instantaneously freezeing the whole universe" is sort of an impossible thing to imagine, because it assumes there is no cosmic speed limit. "Now" has to be defined as a specific moment in time in a particular region of the cosmos (otherwise "Now" means "All of Time"), but that specific, designated region doesn't correspond to, or "link up to" any other specific regions until its light cone has encompassed those regions. You have to first traverse the cosmos, to another distinct region, below the speed of light, to link those two regions together. If you ignore the confines of a lightcone, you're going beyond the speed of light, and thus, you're talking about things that are happening in the future from your lightcone's perspective. So to ignore lightcones and say "freeze everything in the cosmos as once" you're talking about combining your region's present with your regions future too, which is contradictory and extremely head-ache inducing to say the least lol. So you can't just take all regions of the cosmos and say "freeze them all at one moment" because there is no "one moment" except on the skin of a lightcone. The only way to judge what "moment" two regions are in, is by comparing them, relating them, via their overlapping borders of their relative lightcones. So there is no such thing as a universal "now", just like there is no center of the universe. Hope that makes sense. It's pretty tricky to convey with just words.
agc
agc - 19 hours ago
To freeze the universe, you'd have to pick a point in spacetime (a moment / a "now" and a spatial location) to freeze, and then flip the switch. That moment would freeze, and the freeze would expand from that location like an icy sphere at the speed of light. Everything outside that growing sphere would continue to move as usual... until... the sphere finally hits and encompasses it. Freezing it in place. And eventually, the whole universe would be encompassed and frozen to the point of that original moment and location. So you could freeze the whole universe, but it can't be "instantaneous." "Instantaneous" makes no sense in physics. There is no such thing, because there is a cosmic speed limit. And that is what is meant by a "light cone." The light cone is essentially that growing icy sphere, freezing the universe to a particular moment. Everything that gets frozen is the outer edge / skin of the lightcone. But all the motion that occured before it got frozen would be forever outside the lightcone, unknowable to the person at the centre of the lightcone, because light could not encompass it in time. When you look at the sun, you can only see it AS IT WAS 8 minutes ago. But you have to wait until the future, to see what the sun was like this "instant." And by that time, the sun's "now" has shifted another 8 minutes. You will never be able to see the sun as it is THIS INSTANCE because it's just outside your lightcone. You have to let your lightcone evolve by 8 minutes... by which time, the sun has also evolved its own lightcone which is separated from yours by 8 light minutes. You can only know what is going on in eachothers lightcones, when the lightcones overlap to create a shared "now." So "now" is relative, and it depends on the speed of light. So there is no universally shared "now" between you and the sun. The lightcone overlap (and thus the shared "now") changes... it stretches and squashes as the Sun and Earth get closer together and further apart in their orbits. So what constitutes an "instant" in the universe HAS TO depend on your lightcone, and the lightcone of the thing you're trying to share a "instant" with. There is no universal "instance" or moment. It's relative.
Carlos Grant
Carlos Grant - Day ago
I don't think anyone knows for sure. Even in this video Matt doesn't commit to a definite answer. You just have to go with the answer that makes the most sense to you, or prove the others wrong.
SAHM
SAHM - Day ago
Hey Dr. O'Dowd. When you're in a class, and the class ends (especially if it's online), do you say hit like, share and subscribe at the end of it?
Kelvin .Davies
Kelvin .Davies - Day ago
seems abit random is gravity a force ?
AbbreviatedCrook VideosGreg
I've had the thought before that if the past doesn't exist through your type of reasoning, then we could perhaps deny the holocaust in a sense.
stigofdunsfold
stigofdunsfold - Day ago
I now understand Interstellar. I’ve watched videos on this topic so many times but nothing ever quite made sense to me, thank you!
Mark Douglas
Mark Douglas - Day ago
Does anyone fancy a beer ?
JAM BS
JAM BS - Day ago
On one of the Pillars of Creation, will not reveal location, Agni has his deep abode where to visit, one passes slices of time as though a paper thin onion skin. To visit, pass about 1000 sheets but leaving is another story, dimensions quickly shift, don't get caught.
Jeffrey McKinley
Jeffrey McKinley - Day ago
Awesome video. Thanks.
Stephen chadd
Stephen chadd - Day ago
Red pill or blue pill?
Darrel Sapp
Darrel Sapp - Day ago
But, you have the NOW all wrong. I can't do the math, but things don't make since to me unless you include the past and future into the now at the speed of time. Now is effected by the past and future. It's why I feel gravity isn't that, but the change in time.
Neil Williams
Neil Williams - Day ago
Harrp
Neil Williams
Neil Williams - Day ago
Lhc and harry is playing up and messed the universe
Neil Williams
Neil Williams - Day ago
I’m in time travel now it’s like losing ur soul and having trouble getting it in had other souls passed through me and helping them and the magic get in
White Candle
White Candle - Day ago
no, they don't. Everything in existence is exactly where it is at this ONE instant, which will lead to where everything is in the next instant, & the next. There is ONE series of individual "past instances", which leads to the ONE "present instance", which will then lead to the next & the next & the next future instances. Check out the book "The Law of Conservation of Matter for Dummies".
White Candle
White Candle - Day ago
One final note on how to ignore all the malarky. Think of the universe (and all the tiniest of tiny sub atomic particles) as a row of dominoes that are in motion. One domino hits the next, and the next in an orderly predictable manner. Determinism! BUT just because you know things will turn out one particular way does not mean that you will know what that one way is. Since WE don't know how things will turn out, WE still have what WE call free will, despite things going to turn out a particular way.
White Candle
White Candle - Day ago
for those tired of my comments, the bottom line is that there is no "time", there is only a comparison of the relative state of things. If you returned the particles in a rotten apple to the positions of the previous week, the apple would appear fresh, but would still be just as "old" as ever even though re-arranged.
White Candle
White Candle - Day ago
Why keep saying "when looked at the right way", which only means "if we ignore other things that are true".
White Candle
White Candle - Day ago
The successful "calculation" of the sequence of the universe requires a vantage point. BUT, you are NEVER able to make your "vantage point" part of the equation because, if you did, it wouldn't be an independent vantage point and is, thus, meaningless.....Which is to say that the vids mention of having an independent vantage point is meaningless.
White Candle
White Candle - Day ago
I am reminded of the movie Galaxy Quest, where the only possible method of "going to the past" was to take everything that exists and re-arrange it to where it was 13 seconds ago.
Stephen Medley
Stephen Medley - Day ago
I still agree with Newton: there is a universal time , valid for all events . That does not contradict with observations of the past of 13.4 bio Years ago which we detect today.
I also agree with local space time, and that also does not contradict with a universal time. There are only transitions between local space times and universal time.
Billito
Billito - Day ago
Time is white therefore it is racists, we must destroy it immediately. I will be letting blm antifa know of its location.
John Connor
John Connor - Day ago
Time Travel isn't possible
.
On a side note through a simple exercise in logic you can prove that time travel is not possible from the future to the present. Or from the present the past for that matter.
All it takes is a simple exercise in logic.
Ask yourself; Is this 'The Present'? If your answer is yes then 'The Future' has not been created yet so it does not exist yet. Nobody is there to create a time machine. End of story.
If your answer is "No" you have more urgent problems you should be dealing with than theoretical physics.
If by some major dysfunction in reality someone shows up from 'The Future', then conversely this must not be 'The Present'. It would be their ‘Past’ and we would not be living in “The Present”. But we are.
Again end of story.
Sir Squegg
Sir Squegg - Day ago
I haven’t watched yet but I’d guess yes it does exist. If I travel from point A to point B, then halfway through my journey point A still exists I just went past it and point B exists I just haven’t got there yet. Time is as much a part of this universe as matter, so I think that analogy works.
Right I’ll watch now, you better make me wrong. 😂
John Connor
John Connor - Day ago
I don't buy it that time has anything to do with a light cone. The present anywhere is still the present.
Thom P
Thom P - Day ago
Time is simply the observation of motion, it is not a physical characteristic of space. If you remove the observer there is no measurment of time. This is why coma patients have no reference of how long they were in a coma for. In other words, time is an abstract byproduct of conciousness, nothing more. Since every observation starts when it is observed, and since the universe is in constant motion, conciousness can only percieve time in one direction. Time is an illusion of conciousness, simply describing the points in space for which an object is viewed in space relative to its motion.
Carl Ravensbergen
Carl Ravensbergen - Day ago
bro, my brain
Clif B.
Clif B. - Day ago
So does that mean time is not money?
John Connor
John Connor - Day ago
Lets hope so, because as a dedicated procrastinator I've wasted it like a drunken sailor in a Hong Kong brothel.
Patrick b
Patrick b - Day ago
The more I learn the more I understand why my college physics professor said he was a atheist before he got his doctorate and realized that their is no way all this could have happened on its own. Amazing.. oh, now let the haters hate flow. It brings me joy to see their anger.
Matt Mars
Matt Mars - Day ago
Dear professor O’Dowd Re: PBS Space time: Do the Past and Future Exist?
*“IF all that exists is just whatever exists right now, could this be enough to mislead us into incorrectly assuming a “past” and or “future” may exist ?”*
Thank you, and the team, for another very interesting video, describing as you say the rabbit hole concerning the (apparent) nature of time.
With respect however, I think if one investigates your opening question more deeply, and with the very simple experiment described below, it may be shown that “all that exists now” could indeed be enough to explain all that we seem to observe.
M.M.

In, Do the Past and Future Exist? You open by asking,
Is all that exists just whatever exists right now?
And, imho, the answer to that may actually be Yes. But you don’t seem to pursue the question fully, instead just investigating what “the past” and “the future” may be.
I think the problem here is that if we are in fact wrong to assume the existence of a “past” and “future” trying to work out what they may be, will indeed lead to the rabbit hole of conflicting, unproven, unprovable and inconclusive conjecture you describe.
Imo, in any subject significant conflicting conjecture can be a sign of 2 things…

1- We are on to something, and that thing is quite complex, so we should carry on exploring that path, or
2- Or that we may be on a completely wrong track, and thus should recheck all our most basic fundamental observations, opinions and conclusions from the ground up, systematically logically and scientifically, with no sacred cows or unquestioned heroes in the mix, and with experimental proof of every assumption made.
Re point 2, I suggest exploring you question another way such as...
q1: *“IF all that exists is just whatever exists right now, could this be enough to mislead us into incorrectly assuming a “past” and or “future” may exist ?”*
Experiments, instead of just discussion… “the past”?
Re “all that seems to exist”, all I personally fundamentally seem to observe is a vast collection of matter/energy which seems to be moving and interacting, in all directions as per the laws of physics.
With this in mind perhaps try the following simple experiment…
*ep1, Place an object ( e.g. a cup) at the left edge of a table (x).*
*ep2, Look directly at the object and make a mental note of its location.*
*ep3, push the cup from left to right with a finger, very carefully noting what you do and do not actually observe.*
(and relax :)*
I suggest here you do observe the cup moving in the direction it is pushed, and because it is being pushed. And, very specifically I think you will not in any way at all observe any part of the experiment ‘heading into a temporal future’, nor ‘creating or accruing a temporal past’.
These observations may seem naive, but may be critical given that your video mentions the ideas of a past and/or future a lot, but it seems the creation or existence of these things or places is not directly observed. So re this, consider continuing the experiment thus....
*ep4, With the cup at the right of the table carefully consider the following 2 questions…*
*q4.1: Do I have a mental image of the cup at the left of the table in my mind?* And,
*q4.2: Was the cup at the left of the table ‘in the past’?*
I suggest the answer to 4.1 would be, Yes I do have a mental image of the cup to the left, and, for most people the immediate answer to 4.2 would be, Yes the cup was to the left of the table ‘in the past’.
So this may bring up a critical distinction because it seems to me the answer to 4.2 will be entirely based only on the fact pointed to by q4.1.
If you ask someone only seeing ep4 “was the cup to the left of the table ‘in the past’ ” they would probably reply “I don’t know”. And this would be entirely because they have no such mental image. However, if the base of the cup happened to be wet, and able to leave ring marks and drag marks on the table, this other person might respond “yes, the cup was almost certainly to the left ‘in the past’ ”.
The point here being that in both cases it seems that you saying the cup “was at x in the past”, or someone else deducing “the cup was at x in the past”, are both based entirely on observations only of what is present (either the image physically existing in some way in your mind just behind your forehead, or the view of watermarks on the table).
Also, in both cases all that is needed to get these replies, is for matter to exist, move and interact. And in neither case is the existence of an actual temporal past observed or required… even though people may (without any conscious thought ) assume without question that they are apparently legitimately talking about a thing or place called “the past”.
So, for yourself (Matt) as a professional trying to fully understand the problems with the idea of time, it might make sense for you to ask and critically, actually answer for yourself questions like...
*q3, Do I actually have any valid reason to presume that some kind of temporal past exists, and/or is constantly being created and stored in some way, some how by the universe?* And,
*q4, Do I have any valid evidence at all that a temporal record of all events in the universe exists in any way any where?*
(As opposed to just assuming such things may exist and going straight to wondering what they ‘are’.)
*“the Future”?*
*ep5, with the cup to the right (loc y), push it slowly further right, and while doing so ask yourself...*
*q5.1: Can I imagine what the cup would do if I pushed it such that it was over the table edge ?* And,
*q5.2: Can I image what could happen if the Tooth Fairy really existed and she/he wanted a valuable tooth stuck beneath the cup ?*
I suggest the answer to both these questions could be 1 Yes, I can imagine the cup would fall off the table edge. And 2 Yes, If the tooth Fairy really existed she/he might try to grab the trapped tooth as I’m moving the cup.
In both cases for you to construct answers all that is required, and all that will be happening, is that physical matter ( atoms, ions electrons etc ) physically in your head are able to exist move and interact in various ( highly sophisticated ) ways so as to form constructed mental images there.
The point being that in case 1 you may think you are genuinely considering / “predicting” something that may or not come true “in the future”, but in case 2 you see that all you are doing is choosing to construct a random mental image about the scene, which may or may not correlate with the scene... as it ‘is’ changing.
And, in both cases I suggest no kind of future is actually observed “arriving” or being formed. And as suggested in part ep3, it is not observed that the cup is heading into a future, but instead what happens to the cup depends entirely on what physically exists ahead of it, in the direction it is being pushed (e.g. table or no table etc).
*Ep6, Try the above experiment with either a small motorised pointer rotating on a numbered dial, or a swinging pendulum bob, also on the table and as yo do so ask yourself...*
*q6, “Is this rotating pointer (or oscillating pendulum) in anyway scientific evidence that where things are moving and interacting there is also some other “thing” we might call ‘time’ that is ‘passing’ through all locations in the universe, from an unobserved and not required “future” into an unobserved and not required ‘past’, or is this just a pointer moving on a dial as other things in the room and in my body also happen to be moving and changing?”*
I would suggest the answer to q6 is No, it is not such evidence, and, although it may be true that IF a thing called time does exist Then, a smoothly rotating pointer may be a useful analogue of it, a smoothly rotating pointer is not scientific evidence there is a passing thing called we might call ‘time’.
*Ep7, look in a mirror as you are holding a photograph of yourself as a child, (or a copy of Newton’s Principia:) and ask yourself…*
*q7.1 Is the relatively stable pattern of ink on this inert piece of paper, proof that some things (e.g. the image) can be changing more slowly than other things (e.g. my own body) ?*
*Q7.1 or, Is the relatively stable pattern of ink on this inert piece of paper, in some way scientific proof that a temporal past record of all events also exists in another inconceivable “dimension” or place ?*
Einstein’s Relativity…
All of the above is of course moot if it doesn’t incorporate the experimentally proven and very consistently implemented aspects of Relativity.
Re this I suggest reviewing Einstein’s “On The Electrodynamics of Moving Bodies” very carefully, and from 2 perspectives…
*1, That there may be a thing called time, and e.g. that a rapidly accelerating light box (I.e. a photon trapped between to mirrors) in some way shows time’s passing, and also that it’s passing can be dilated.*
And,
*2, Or, That matter may just and only be existing moving and interacting and a rapidly moving light box as above may only show that fast moving things “are” just changing “now” more, slowly than intuitively assumed… in which case a future, a past, and passing time may not be required, or shown by Relativity.*
Just some thoughts, thanks again for the great vids, got to go, run out of YouTube comment space.
Matt Marsden
Matt Mars
Matt Mars - 15 hours ago
@John Connor Hi John, thank you for your reply :) You may be missing the point if you do that. What I am saying is... If we don't see any evidence at all of a 'temporal past' actually existing, or being created or stored anywhere, and if we don't see any evidence at all of a 'future' constantly arriving or being headed into, then it is not scientific or logical to just assume 'their' existence and endlessly speculate about what they may be. But instead perhaps it makes sense to also very carefully explore whether the universe, just as it seems to be, is enough to mislead us into incorrectly assuming these things exist, if we don't examine the evidence we do have carefully enough. So you may be better off taking it as a "Are you aware of this possibility? and considering it carefully?" Matt.M.
John Connor
John Connor - Day ago
So I'll take that as a 'no'?
SpatioTemporalEntity
The past is no more in as much as the future is not yet, there is no tense other than the present.
Friendy Advice
Friendy Advice - Day ago
This guy is seriously bright
Pons Cardinal
Pons Cardinal - Day ago
You are talking to kids. Dont confuse them while earning a living.
Rob Tapper
Rob Tapper - Day ago
We are "the observers" --- the failure of pyhsics is to configure observers in their pursuits. Where did the "observer" exist in the origin of the universe?
Alioth Ancalagon
Alioth Ancalagon - Day ago
Its super hard to even come up with a proper common ground what the "present" even is.
You can also argue that our present is not what we can see from Betelgeuse right now, simply because our information is 530 years old and account for that.
Don't get me wrong past light cones and future light cones are real. But that doesn't mean that they have to be the foundation of the "present".
That a letter from someone reaches you just now, does not mean that he just wrote it. In everyday context nobody would agree with such a definition of the "present".
Laurie Dooker
Laurie Dooker - Day ago
Can’t believe in multiverses if we live in a real physical world. All that energy to destroy what was , just to create another.? Because I killed my grandfather before father was born? Madness unless we don’t live in a physical world . Only then is it possible. Once something has come into reality it will continue to exist until it’s Destroyed after it was made not before. A thought is like a dream it has no real mass. Multiverse,multiples of the same earths ? It’s on the bottom of my list of probably outcomes of time travel.
Dan Kelly
Dan Kelly - Day ago
Wouldn't a time slice be a cube? (Assuming 3 spatial dimensions only and assuming the concept of dimensions is relevant to the universe).
The Official Music Videos
Mind Blowing Stuff. Great Video Bro. stay safe and look after yourself. have a great day
electroislove
electroislove - Day ago
I want to thank you for the content you create! You never fail to strengthen my passion for physics :)
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