If Time is Emergent, why does Present follow from Past?

[maarsen]

By observing aren't you interacting with the universe in some way? For example to actually see this universe light must travel from it to yourself, and if light can do that then you aren't outside of the universe.

Existing in the universe is interacting with it.

[Anatúrinbor]

Yeah, but is it true that to observe the universe you need to interact with it, and that can't be done unless you exist in the universe?

[bbstark]

Thanks for the link. [but not sure what retrocausality has to do with my OP?] What do you think is unclear about my question?

Eta: How about "If the universe is static to the outside observer isn't it a low probability event that internal observers live in a universe that makes sense?"

I had to read parts of the paper before your question in the title made sense, and before I figured out whether or not the paper can answer your question. "present follow from the past" to me implies that time is ordered and increasing in one direction. Answering "why" that is, is quite a feat, and I wasn't sure if the paper addressed it. It doesn't. However a bit of googling lead to another work.

Bear in mind I don't actually use that kind of quantum calculations in my research. Though I know what theoretically "preparing a quantum state" means, I've never actually created or even handled a nitrogen vacancy in diamond (or any other method to do that) let alone performed qubit calculations.

I believe to truly understand something you need to be as thorough and accurate as possible. I don't like vagueness, least of all in physics.

Happy to help as much as I can though.

the eta part: this question is unclear. As far as I know the research is predicated on the assumption that the laws of physics are the same inside and outside the universe. Is that what you mean by "universe that makes sense"? this is the kind of writing that is very difficult to parse in physics. Say exactly what you mean.

[maarsen]

Yeah, but is it true that to observe the universe you need to interact with it, and that can't be done unless you exist in the universe?

Probably yes.

[Sci-2]

@BBstark:

Happy to help as much as I can though.

Thanks!

the eta part: this question is unclear. As far as I know the research is predicated on the assumption that the laws of physics are the same inside and outside the universe. Is that what you mean by "universe that makes sense"? this is the kind of writing that is very difficult to parse in physics. Say exactly what you mean.

I've been pondering this issue. I think the problem, for me at least, is that without time why is there apparent causality and witnessing of motion?

Last night I came across this presentation by Julian Barbour which goes into this question of time.

[He elucidates the issue better than I can, particularly in the last 10-15 minutes.]

Julian Barbour, visiting professor at the University of Oxford and the author of The End of Time, addresses the question, Does Time Exist? Barbour explores the history of scientific thought on the concept of time and presents his own interpretations of what time is.

[Lily Valley]

Nice article Sci. I'm trying to follow up on this and get some more detailed information. One big minus for pseudoscience is that it has cluttered google with irrelevant articles that make research a little harder. Here's the original article for the other scientists out there. It's math heavy. Very. However it has a detailed description and diagram of the experiment. It also gives some history on the quantum problem of time.

It does looks like Entropy was put forward as the phenomena responsible for an emergent theory on gravity.

[Sci-2]

It does looks like Entropy was put forward as the phenomena responsible for an emergent theory on gravity.

Cool, thanks for that!

Julian Barbour talks more about his ideas on time being illusory in this video, A New Kind of Causality. I started watching this last night but it keeps cutting out for me.

"There are serious indications from attempts to create a quantum theory of gravity that time must disappear completely from the description of the quantum universe. This has been known since 1967, when DeWitt discovered the Wheeler-DeWitt equation.

I shall argue that this forces us to conceive explanation and causality in an entirely new way. The present can no longer be understood as the consequence of the past. Instead, I shall suggest that one may have to distinguish possible presents on the basis of their intrinsic structure, not on the basis of an assumed temporal ordering. If correct, this could have far-reaching implications. Hitherto, because the present has always been interpreted as the lawful consequence of the past, science has made no attempt to answer 'Why' questions, only 'How' questions. But if there is no past in the traditional sense, we must consider things differently. Thus, if we eliminate time, we may even be able to start asking "Why" questions."

[Weeping Sore]

Reading a little about black holes and the action of matter in the accretion disc, matter begins to approach the speed of light as it gets closer to the singularity. And the closer it gets to C, the slower time passes. Then (oops, linear time-word) once matter or energy reaches the singularity it ceases to be matter or energy or even space-time.

So what appears to be the gradual siphoning-off of matter into a black hole (i.e., a process that appears to take time) could explode everything that will ever go into the black hole into somethingness in an instant not unlike our Big Bang. (that's assuming there's another "side" of a black hole, not just oblivion)

Not sure if that really solves for the meaning of causality without linear time, just a real macro example of time breaking down.

[Lily Valley]

I just gave a VERY basic lecture on special relativity. Relativity holds up consistently. Layman's relativity shows anyone who can solve the pythagorean theorem that photons must exist outside of time. In addition, travelling faster than the speed of light puts you right smack at the square root of -1. That shit's not real. Time is weird.

Any grad student who had to resolve resolve relativity with electrmagnetic theory will just shudder in horror at the mention of time problems. I'll bet that if you google the phrase "retarded time" it will just show physics students throwing up.

My quantum physics is rusty and never got past the early papers of the 1940's. That said, there's several good courses available that have a multilevel approach to quantum physics. Many of them can be followed without doing 30 hours of differential calculus every week. MIT has their entire program available online through grad school. It won't do most people much good, as most of their courses are only notes and homework with reading material. Trust me, most people need peers, a professor and lectures to figure out whether or not the "reading material" for most quantum physics is upside down or not.

I'm on a stupid phone right now, but will post the relevant links when I can.

My favorite is www.coursera.org. they don't often have GOOD quantum classes open, but when they do they're worth the time.

Edited for changing tenses twice in each sentence.

[Sci-2]

The Unreality of Time By John Ellis McTaggart

I'll be honest and say I don't get some of the arguments. But curious how others respond and don't want to color the results with my possibly erroneous reasoning.

It doubtless seems highly paradoxical to assert that Time is unreal, and that all statements which involve its reality are erroneous. Such an assertion involves a far greater departure from the natural position of mankind than is involved in the assertion of the unreality of Space or of the unreality of Matter. So decisive a breach with that natural position is not to be lightly accepted. And yet in all ages the belief in the unreality of time has proved singularly attractive.

In the philosophy and religion of the East we find that this doctrine is of cardinal importance. And in the West, where philosophy and religion are less closely connected, we find that the same doctrine continually recurs, both among philosophers and among theologians. Theology never holds itself apart from mysticism for any long period, and almost all mysticism denies the reality of time. In philosophy, again, time is treated as unreal by Spinoza, by Kant, by Hegel, and by Schopenhauer. In the philosophy of the present day the two most important movements (excluding those which are as yet merely critical) are those which look to Hegel and to Mr. Bradley. And both of these schools deny the reality of time. Such a concurrence of opinion cannot be denied to be highly significant -- and is not the less significant because the doctrine takes such different forms, and is supported by such different arguments.

I believe that time is unreal. But I do so for reasons which are not, I think, employed by any of the philosophers whom I have mentioned, and I propose to explain my reasons in this paper.

[Weeping Sore]

It's ironic that we have to post on this thread in chronological order.

[Sci-2]

It's ironic that we have to post on this thread in chronological order.

Heheheheh. Was discussing the Unreality of Time essay with a friend who actually has a physics degree, and he put me on to this:

Chapman University scientists introduce new cosmic connectivity

There are different types of non-locality which quantum mechanics showed could not exist in classical physics. In classical physics for a particle to experience a force, it must be at the same location where the force is. In quantum mechanics you can have a force in one place while the particle moves outside. Nevertheless, the particle will still feel this force. This is called the Aharonov-Bohm effect.

There is another kind of non-locality that has to do with the relation between two particles that used to be next to each other in the past and then subsequently were separated to a large distance. Even after they were separated far apart, they appeared to maintain a strange kind of connection—what Einstein called “spooky action at a distance.” However, these surprising kinds of connections had many limitations. For example, the particles had to originally be next to each other and only a relatively small number of particles in the universe could be connected with each other at a time.

While the above was remarkable enough, now it appears this was only part of the story as demonstrated in a recent paper by a team from the Institute for Quantum Studies at Chapman University co-authored by Yakir Aharonov, Fabrizio Colombo, Sandu Popescu, Irene Sabadini, Daniele Struppa, and Jeff Tollaksen. They introduced a new kind of quantum connectivity between particles which transcends these limitations. This connectivity is happening all the time on a much bigger, cosmic scale.

“With the new kind of quantum linkages which we have introduced, the particles don’t have to interact in the past. In fact, they have no idea that the other particle even existed,” said Jeff Tollaksen, Director of the Institute for Quantum Studies at Chapman University.

Aharonov turned Einstein’s question around and asked, “Why does God play dice?” He found that Nature gains something very beautiful and exciting with this indeterminism: the present is not only affected by the past but it is also affected by the future. That is, the future (also known as post-selection) can come back to the present (like in the movie “Back to the Future”). So quantum mechanics does not pick out an arrow of time, it works just as well from past to future as from future to past. The quantum world links the future with the past in subtle and significant ways; and in dramatic contrast to everything previously known about time.

[Sci-2]

The Evolution of the Laws of Physics - Lee Smolin

A lecture drawing upon ideas Smolin discusses in his book Time Reborn.

[maarsen]

Time has always fascinated me because it is so arbitrary. As stated above QM does not need time to run in any one direction and causality need not have a direction either. Couple this with the idea that the human brain uses quantum effects to do what it does and one could plausibly show that precognition exists.

Another idea is that as all information is encoded on to physical particles, as time passes, information imprinted earlier must at some point be erased and new info imprinted. Does this imply that the past is as indeterminate as the future? Or does the determination of the past imply the determination of the future?

[Sci-2]

Great questions Maarsen - I admit that while I find the idea of possible pasts really cool b/c I'm a[n] SFF fanboi, I cannot even begin to comprehend how to make sense of such a thing.

I'm reading about Bergson and Whitehead*'s philosophies and their relationship to contemporary cosmology. A big point for both of them seems to be the fact that something is left out by our attempts to quantify time as a river of frozen moments. This seems to be in accord with Freya Matthews, who I mentioned in the Religion Thread, discussing how abstraction via theories is less a perfect capturing of reality than a sieve from which various important contents trickle out. [Recalls Jaron Lanier's essays on consciousness as well.]

I'll try to say more on that when I have a better grasp on their works.

*At least one work of Whitehead's is a freebie!:

Science and the Modern World. Lowell lectures, 1925, by Alfred North Whitehead.

=-=-=

A New Theory of Time

Is it possible that time is real, and that the laws of physics are not fixed? Lee Smolin, A C Grayling, Gillian Tett, and Bronwen Maddox explore the implications of such a profound re-think of the natural and social sciences, and consider how it might impact the way we think about surviving the future.

Full event, Q&A available by following link in comments.

[maarsen]

Great questions Maarsen - I admit that while I find the idea of possible pasts really cool b/c I'm a[n] SFF fanboi, I cannot even begin to comprehend how to make sense of such a thing.

I'm reading about Bergson and Whitehead*'s philosophies and their relationship to contemporary cosmology. A big point for both of them seems to be the fact that something is left out by our attempts to quantify time as a river of frozen moments. This seems to be in accord with Freya Matthews, who I mentioned in the Religion Thread, discussing how abstraction via theories is less a perfect capturing of reality than a sieve from which various important contents trickle out. [Recalls Jaron Lanier's essays on consciousness as well.]

I'll try to say more on that when I have a better grasp on their works.

*At least one work of Whitehead's is a freebie!:

Science and the Modern World. Lowell lectures, 1925, by Alfred North Whitehead.

=-=-=

A New Theory of Time

Sci, I have a bit of a confession to make. I have been pulling your chain a leetle bit in this and other forums, but only because I find your stuff really cool and I enjoy reading it. It is a failing that I have in that I find try to find humour in even the most serious of subjects. As Bill S. said "many a true word is spoken in jest." I thought you would have caught on when I posted my algorithm on how to be funny.

Seriously though, if the many worlds hypothesis can be considered valid, why cannot the validity go in both directions, past and future. This could explain why so many conflicting versions of past events can not be resolved no matter how much research is done. :cheers:

[Sci-2]

Oh, I took it seriously b/c I swear I read a theory of time that allowed for a malleable past at a microscopic level. I think this actually had to do with some of the weird stuff that comes up in QM.

Possibly something a physicist friend sent me about Time Symmetric QM. (He said that he didn't think it was necessarily correct, but that this kind of thinking might help us get to a better understanding of time.)

Anyway, I think Many Worlds is completely wrongheaded, partially for reasons IHT & others gave here.

[The Anti-Targ]

Science confirming religion again. Religion has always said that time is an artifact of the physical reality and that the metaphysical reality is without time.

So add that to evolution, nuclear chemistry (aka alchemy) and the abundance of the existence of planets in the universe as things which religion stated as truths which science later confirmed.

It's good to see religion and science continuing to come together in harmony.

[Sci-2]

I thought you would have caught on when I posted my algorithm on how to be funny.

I missed this completely. Where was this?

Science confirming religion again. Religion has always said that time is an artifact of the physical reality and that the metaphysical reality is without time.

So add that to evolution, nuclear chemistry (aka alchemy) and the abundance of the existence of planets in the universe as things which religion stated as truths which science later confirmed.

It's good to see religion and science continuing to come together in harmony.

So you think all things have already happened because all time occurs in a simultaneous moment, or that attempting to set a description to the nature of time in any way is doomed to failure b/c we're too limited?

[The Anti-Targ]

I missed this completely. Where was this?

So you think all things have already happened because all time occurs in a simultaneous moment, or that attempting to set a description to the nature of time in any way is doomed to failure b/c we're too limited?

I certainly think our puny minds are individually and collectively too weak to understand the true reality of things. My brother is a physics PhD and was literally a rocket scientist for a few years over in Florida. He once told me that some mathematicians reckon that of all the maths that exists in the abstract, the amount humanity collectively knows might as well be considered as nothing because its such a tiny nano-fraction of what could potentially be known. If maths is the foundation of science then that means our knowledge of the other sciences is as equally empty and void, and since science is our only way of discovering the reality of our physical universe then our knowledge of the reality of things is more or less nil.

He also said that as the quantum level time flows equally well in both directions, so it really is only our perception of time that has it flowing in one direction

Add to that, for argument's sake, that metaphysical reality exists, we know less about metaphysical reality than physical reality. So much less in fact that many millions of people deny the possibility of its existence. Which probably says more about the arrogance of humanity than what is objectively true.

If time does not exit outside of the physical reality, then "instant", "simultaneous", and "moment" are meaningless terms in that reality, as they all have a temporal aspect. So I don't think that everything happens all at once, but my mind is too small to conceive of the interplay between a tempral reality and an atemporal reality.

We kind of know that there is an atemporal reality, because we know that time is subject to relativistic effects. The faster you go the slower time flows, and once you reach the speed of light time stops. Does that mean if the speed of light is not an absolute speed limit it means going faster than that causes time to flow in the other direction?

My brother formulated an hypothesis about fundamental particles interacting with themselves by moving backwards in time as well as forwards, he reckons this is part of the solution to the geon hypothesis which is part of the whole question about gravity. His problem is that he doesn't understand the mathematics that is necessary to really work it out. Which is usually where most physicists fall down, they are just amateurs when it comes to maths.