So you agree that the light existed before it hit your eye. Yes or no?
Correct, but I am asking another question.
Both wrong. Unknown is correct.
See my above answer.
That is not how rational agents behave. The whole reason you have a brain is to make predictions about the future, and in order to do that you have to model the world.
If the light hits my eye at t=0, that means at t=-1 it was traveling towards my eye, it didn’t just materialize in my eye at t=0. In order to make a prediction of what will happen at t=10 we have to consider what was likely happening at t=-10.
You can’t just say “unknown”. Just because we don’t know for certain doesn’t mean we can’t make a model of what was likely happening.
Both cannot be wrong! Either the light existed before hitting your eye, or it didn’t. Let me ask you another question: There was an apple on the table before you ate it. Did the apple exist or not before you ate it?
I’m late to this long thread so apologies if I’m repeating stuff that’s already been said.
John Archibald Wheeler proposed a thought experiment based on the famous two-slit experiment in order to test the foundations of quantum mechanics. The issue to be investigated was the fact that the availability of so-called “which way” information (which slit the photon goes through) changed the outcome of the experiment.
Wheeler’s version consisted of delaying the decision as to whether or not to have the “which way” information, until the photon has already passed through the apparatus.
When Wheeler’s thought experiment was eventually performed, it turned out that even this delayed choice affected the outcome, as though the delayed choice were retrocausal in some way.
Wheeler rejected the idea of retrocausality. His conclusion was that present actions actually generate past events (note the word ‘generate’ – this avoids the confusion of implying that a particular past event ‘exists’ and is subsequently changed).
Carlo Rovelli’s Thermal Time Hypothesis resonates with Wheeler’s interpretation in that Rovelli postulates that time as we experience it is an emergent property that arises from the Second Law of Thermodynamics, along with the fact that we have incomplete information about the rest of the cosmos. “Before” and “after” are not fundamental, but a consequence of the fact that we live in a cosmos in which TD2 operates.
Bryce DeWitt attempted to reconcile general relativity with quantum mechanics, and with the help of John Wheeler came up with the wave equation for the entire cosmos – the Wheeler-DeWitt Equation. The confounding thing was that the time does not appear in this equation.
Robert Griffiths addressed quantum indeterminacy (Heisenberg uncertainty relations) by proposing that Hilbert space is divided into what he called “frameworks.” Working within a single framework, all operators commute so there is no indeterminacy. But when we switch frameworks, as when we measure position and then momentum, the operators don’t commute, and quantum indeterminacy enters the fray.
Griffiths develops an interpretation of quantum mechanics called the consistent histories interpretation from this approach. He concludes that we must reject the idea of “unicity” – the idea that there is a “real world” that we simply discover as we go along. In other words, we are continually creating the world.
A picture emerges of a cosmos in which genuine novelty is entering by virtue of ongoing activity, creating even the past, so we are constructing the world rather than discovering it. Thermodynamics is the process by which change is given an “arrow” – i.e. by which change becomes time.
A specious argument against Wheeler’s view is that there is a bootstrap problem if we postulate that we are generating the cosmos, and that the cosmos gives rise to us. Wheeler was far from stupid, and he does address this issue.
DeWitt, Wheeler, Rovelli, and Griffiths are renowned theoretical physicists so dismiss this stuff at your peril. I’m not a physicist so the best I can say is that it intrigues me.
Edit: I neglected to mention the Suarez-Scarani “before-before” experiment in which beam-splitters were used in moving reference frames. The idea was to see if quantum correlations were reference-frame dependent. The results reinforced those of the Aspect experiment (experimental evidence of Bell’s Theorem eliminating the hidden variables hypothesis), but furthermore, Suarez claimed their own results show that quantum correlations originate from outside of space-time.
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I am not saying don’t make prediction. But you must be able to make prediction with the valid data and ground.
If you just wantonly keep making unrealistic predictions with no enough data or little ground then you would be either a witchcrafter or brainless.
The stars in another galaxies have been emitting lights millions years ago. They have not reached your eyes yet.
I was presuming that your question was not about after the light has entered your eyes. If that were the case, the answer is already in the question.
How could you know what lights are still coming to your eyes or have existed while they are still making their way somewhere in another galaxies into the earth?
Would you say you know for sure what lights are coming into you? Or are you making wanton predictions like the witchcrafters?
You need to explain what these questions got to do with proving existence and nature of time. Does time exist? Yes or No?
Is time your perception? Yes or No? Please explain why it is or not.
We just need reasons why you are saying it is, or it is not.
You cannot just keep asking questions which sound odd and irrelevant in the middle of discussing on the topic.
Please remember lights from the stars are not time itself.
Apples on the table you ate are not time itself either.
If you are saying they are, then you need to explain on the relation, or the reason why they are time.
But that is exactly what we do. If we observe an object moving towards us with x% the speed of light, we can calculate how much time it will take to reach us, and after said time we check, and we verify the observation matches our model. Every. Single. Time.
So you observed the object moving, and time from the movement. The object, movement and the speed of light or the instrument used, none of them are time itself.
Your perception and the calculation have given you the figure. Is it what you call “time”?
No. The correct notion of “time” is a hundred steps ahead of what you seemingly understand.
That’s why people are asking you a very simple question: does the object we predict will arrive at t=0 exist at t=-1?
It’s a very simple “yes” or “no” queston.
I am talking about a light that hits your eye. Did the light exist before it hit your eye?
OK, let’s say the light existed before it hit your eye. How is it related to existence of time? Is time your perception or physical entity in the world? What is your thought?
I was trying to extend your thought experiment by which you conclude that we exist in the past, bringing you to a contradiction. If you exist in the past moment, when the light hit your eye, then you exist in the past moment before the light hit your eyes, etc. You cannot exist on all these moments. You exist only at one moment, which people call it now that is distinct from the past. We existed in the past, but the past does not exist, so we cannot possibly exist in it.
That’s quite a discovery… or creation. 
So if the past can be changed at the level of fundamental physics, does it matter at other levels? Forward-moving waves are partly moving backwards, as some of the water-molecules roll forwards and others backwards depending on when and where you look.
But the light which hit your eye, and the existence of the star is not in the same time frame. So it doesn’t imply you exist in the past.
My point is the past and future are your perception, and you can only remember your own experience and imagine the contents inside your mind.
Of course, we are talking about a chain of events that occurred in the past.
But you claimed that we exist in the past.
The past and future do not exist. We just have a memory of the past and anticipate the future.
Yes, but it doesn’t exist in reality.
If past is your perception, how can you exist in it? You can control what you want to remember in your memory, but you cannot exist in it physically.
Never said it. Maybe someone else said it?
Well, that was my point. We seem to have agreement after long detour for some unknown reason. Must have been some communication problem somewhere.
Apparently it is not well understood. Under relativity theory, the two observers are merely moving a 0.5c relative to each other. There is no stationary one and a moving one. As for the present, both observers have identical concepts of time (opinions notwithstanding). Both observers experience 1 second per second, and at every event of their lives, consider that event to be the present.
Your wording suggests a more absolute notion of time and space where on observer is the one moving and the other not.
All depend on one’s definitions, which is most often omitted when making such assertions. I don’t consider time to be real simply because I’m not a realist (about pretty much anything). So I’d ask what time might actually be, but I don’t really care if it is designated as real or not. But that’s me.
But then it gets even trickier, because if you understand the physics behind the twin paradox, the only way to properly resolve it is if we live in a block universe.
The twins thing (and the Andromeda one, the Muon one, and all the others) resolves just fine in an absolute interpretation of physics. One simply chooses an arbitrary frame and assert it to be the preferred one.
The premises of relativity have never been proven. That’s why they’re called premises.
So both the past and the future are as real as the present.
That could be true even under absolutism. Anyway, that statement has never been demonstrated. I see no reason to complicate things by assuming otherwise, but the proponents of presentism don’t see their view as an addition (a complication).
LET does a nice job of all those experiments. If you want an alternative to GR, you have to wait almost a century beyond GR theory, but it’s out there. They finally generalized LET.
I can easily stamp a time on any event, even ones that haven’t happened. I can talk about an appointment tomorrow, which is a labeled event that hasn’t happened.
Did he say that? How is it then that the moon can be full, but Venus cannot? What can ‘orbits Earth between us and the Sun’ possibly mean?
Ah, so absolute simultaneity is being labeled as ‘true’ here. This is an assertion that Einstein is wrong, no?
Actually it’s the absolute ones that fail on black holes. Relativity predicted them. Both interpretations seem to work fine with the rest of your list (but only GR supports a big bang). I have no idea why dark matter is on there since it seems to have no relevance to the theory at all. It’s just a different kind of stuff.
As for special relativity/LET, neither handle gravity, mass, or energy. It’s the special case of the absence of all that.
This is correct. Hence the 2nd premise of SR being a premise instead of something actually having been demonstrated.
Are they now? When did this happen? Did you mention this to dismiss the Muon experiments? Are you of the opinion that the ‘correct’ view makes a different prediction?
No, not changed, generated. To regard the past as something that can or cannot be changed is to assume that it exists as what Griffiths calls “unicity” – that the whole thing is already there. Wheeler’s “surprise” version of the game of Twenty Questions is instructive here…
Wheeler envisions the game played in a way where the object is not prescribed up front. Rather, the player asks the first question and the respondent simply gives a random yes/no answer.
When the player asks the second question, the respondent makes the same move, except with the condition that the second reply must be consistent with the first reply. The game continues in this manner until all twenty questions have been asked and answered in a consistent sequence, and the player makes a guess.
The player has not made a guess about an object that had been chosen up front. The player has brought the object into existence through a series of yes/no answers. Wheeler posits that this is our role as “agents” – to bring the world into existence by virtue of the questions we ask of it.
The classic example of this is that we choose an experimental setup that tells us light is a particle, or one that tells us light is a wave. It has long been acknowledged that the nature of light depends on the question we ask, and the revelation that Wheeler’s delayed choice experiment drops on us is that the nature of what we are asking about is created in the act of our asking. It is not retrocausality.
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