What or how did everything start?

[Polymath257]

But is still a matter of contention amongst physicists and philosophers I hear.

Philosophers, maybe. Not physicists.

From our perspective there is a now. From the pov of outside the B theory box it seems it would all be now.

Not quite. But this is also where I don't like the A/B theory distinction.

In the A theory, the past no longer exists and the future does not yet exist.

In the B theory, they all exist.

But philosophers like to say the A theory is tensed and the B theory is untensed. But that isn't how it works in physics.

So, in physics, all of space and time exist. We can talk about an event 2 years ago that happened in Paris and that makes sense to talk about today. We can talk about the eclipse that will happen next year in Mexico and that also makes sense to talk about today.

So, in that sense, the physicist default is the B theory: that the future and past do exist in a meaningful way and we can talk about them.

But, and this is where the philosopher's distinction seems strange to me, physicists can *also* talk about tense: we can talk about the future of any particular event. So, I, right now, am in the future of me yesterday. And I, right now, am in the past of me tomorrow.

There is no *absolute* past and future: the past and future are always linked to some particular event. The dinosaurs are in our past and we are in their future.

More specifically, each event (location and time) has what are known as the past and future light cones: something can contribute to the causes of an event only if it is in the past light cone and the event 'now' can contribute causally to another event only if that other event is in the future light cone of 'here and now'.

What are the findings in physics that point to the B theory?

There are a number of different things we have discovered. For example, we can measure time intervals. But the time intervals measured deeper in a gravitational well have different lengths than those measured further out. In essence, time 'flows' slower on the ground floor of a building than it does on the top floor. This is an actually measured effect.

Another: let my 'here and now' be event X and another event (time and location) be event Y. it is possible for me to measure Y as being in my past (the time on my clock is earlier for event Y than for X) but for someone else to measure it in my future (their clock measurements put Y after X).

In other words, whether an event is in the past or future depends on the observer. Again, this is a measured effect. There is no doubt that it does in fact happen.

So determinism is true whether there is a God who knows the future or not?
I can see that possibility for the physical but if beings exist who have self determination, it seems that would upset determinism even in B theory.

That depends on what, precisely, 'self-determination' means. But that is a completely different discussion.

It does look that way to an extent at least.

You seem to be working with your mind made up about B theory.

Well, there are 'arrows of time' even in a B theory context, at least if you are doing things like physicists. Entropy is still more in the future light cone and not in the past light cone.

And the direction of our memory seems to be linked with that direction given by entropy. We remember the past and not the future because of the arrow of time given by entropy.

Interesting

 

[Polymath257]

That you never reach the end of the even series or the odd series or the 2 combined into one set of counting numbers. So we can't just split it in 2.

Who needs to 'reach the end'? I can say whether any individual number is even or odd. So I know which of the two infinite sets any particular number belongs to. I don't need to *list* the numbers to know this, so the sets are defined even without being listed. Reaching the end isn't relevant.

Hmm I don't like that attempt.
Somebody was trying to explain infinite regression and eternity of time in the past to me and used the example of a rope that was infinitely long in both directions and we cut it, meaning that it was infinitely long in one direction and in the other. You could certainly add to the length of infinity by adding to the length of each piece of rope but "to my way of thinking" and when I try to debunk it, it would mean that a piece of rope cannot be infinitely long in both direction if we can add to it.

And that seems to be a sticking point for you. Let's first address, then, what it means to be 'finite'. To be infinite will just mean 'not finite'.

So, to be a finite set means there is some counting number that 'counts' the number of things in the set. To have a finite length of rope means there is some finite length (a real number) that says how many meters long it is (or yards, or miles, etc).

So, time would be finite into the past if it was possible to go back only some interval into the past and no further. So, maybe it is only possible to go back 14 billion years, but NOT 15 billion years. That would be what it would mean for time to be finite into the past.

On the other hand, if it is the case that no matter how far back you go, it meakes sense to go another year back, then time is infinite into the past.

When it comes to time with "now" as the point of cut (in time) I would say that we would not be at this point in time yet if there was an infinity of time in the past, and we would never come to eternity in the future if we started now.

Why would we not be at this point? To have an infinity of time in the past simply means that at any point in the past, it is possible to go further into the past.

It does NOT say that there is a time that is infinitely far into the past. That is a very different thing.

Yes and no. Splitting it in half implies a finite number that could be split, but infinite just keeps going and going.

Why would it imply a finite number? It seems that you don't like to think of the set of even numbers as a completed entity. All I need for it to make sense is to be able to say, for each number, whether it is in the set or not in the set. i can do that without ambiguity, so the set of even numbers makes sense and is a 'completed object'. Similarly for the set of odd numbers. And it is possible to put those sets that do not overlap together and make another infinite set that is the set of counting numbers.

I no doubt would need to put some time and effort into working on that.

I'm curious what you will find out.

 

[Heyo]

Philosophers, maybe. Not physicists.

Depends on which kind of physicists who hang around with. B time is not really compatible with quantum randomness and the Many Worlds Interpretation isn't B time, is it?
It also isn't A time, that's for sure.
I have a feeling that we need a third option, ideally one that saves causality somehow.

 

[Brian2]

B theory of time doesn't prevent god from existing in the beginning, just before the beginning. But it also says that god can't have caused the beginning.

If God just is, no time, changeless, then the beginning covers anything that could be called before the beginning. God knew what He was going to do and then did it in an instant, time being created in that instant.
It's like looking at midnight. In an instant it is AM, the next day begins.

 

[Brian2]

I'm not sure how a 'box' is relevant. And, you are assuming there is time before the BB. That isn't clear.

How did the BB happen from cause and effect if there was no time for cause and effect to exist in.

There was no 'point' of origin.

So everything existed in space/time and we just travel through that space/time and I guess as we are doing that, at a different space/time coordinate we are still doing what we have just finished doing in our particular existence. So our whole life is set in stone but continually on the move from one cause/effect to another. And origin is a silly term because it has always been that way,,,,,,,,,,,,,,it just is.
Hmmm interesting

yes. Correspondence with observation is part of the definition of 'true'.

How does matter effecting the geometry of space/time demonstrate that the B theory is correct.

 

[viole]

But is still a matter of contention amongst physicists and philosophers I hear.

As many things in science, and philosophy. However, currently it is a very live option. I would say, without viable alternatives, if relativity is true.

From our perspective there is a now. From the pov of outside the B theory box it seems it would all be now.

Not from our perspective. From your perspective. Different observers cannot possibly agree on what “now” is, since there is not such a thing as simultaneity. Even if you were 1 meter from me, I would still talk with someone in my past. And what lies in the now from one observer, might be in the past of another, and the future of another.

What are the findings in physics that point to the B theory?

Relativity, mainly. If relativity is true, then A theory is false. The fact that spacetime can have a geometry influenced by things like mass, also indicates that it is part of the physical world. And thing like spacetime cannot possibly change, not have n age, by definition. Ergo, the universe is eternal and unchanging.

it is not the case, like at the time of Newton, that space and time where almost metaphysical absolutes providing a context for the physical world. Now they are themselves physical objects subject themselves to some differential equations.

So determinism is true whether there is a God who knows the future or not?
I can see that possibility for the physical but if beings exist who have self determination, it seems that would upset determinism even in B theory.

If it is true, as it is if relativity is true, then what you are choosing to do on the weekend, is in the past of some other observer. And since pasts cannot be changed, what you will decide cannot be changed. That is just a logical consequence of relativity.

that is just a consequence of the Andromeda paradox. And the fact that all other theories entail unitarianism, ergo the conservation of physical information in the universe (e.g. you cannot possibly do something physical that is not already entailed in the status of the universe before your birth), all conclusions match nicely: the future is perfectly determined by prior states. That is also valid under A theory.

And what self determination are you talking about? What is the self, if not an emergent property of something fundamentally physical, and therefore subject to the same nomological rules?

You seem to be working with your mind made up about B theory.

To be honest, I don’t think it is the whole story. For instance, QM does not fit so well in it, even though it still entails determinism (in a different configuration space). However, current research trying to harmonize relativity and QM, seem to entail a form of eternalism, too. What I am almost sure is that time has become part of the physical for good, and not a mere external stage. And since it is difficult to imagine time changing with time, I expect B theory, or a variant thereof, will win. For sure, A theory has no chance, anymore.

And for what concern first cause arguments, I pull out B theory only when I am lazy, since it is a sudden killer of outdated cosmological arguments like Kalam. However, that is not fun. It would be like dueling with someone with a knife by using an atomic bomb. So, when I am not lazy, I rather challenge differently. Kalam, and similars, is great as a study case showing how many independent avenues, from science to simple logic, can lead to its utter destruction in just a few moves.

Ciao

- viole

 

[Polymath257]

How did the BB happen from cause and effect if there was no time for cause and effect to exist in.

Precisely. It was not caused because it could not be caused. it just is.

So everything existed in space/time and we just travel through that space/time and I guess as we are doing that, at a different space/time coordinate we are still doing what we have just finished doing in our particular existence. So our whole life is set in stone but continually on the move from one cause/effect to another. And origin is a silly term because it has always been that way,,,,,,,,,,,,,,it just is.
Hmmm interesting

That is the strictly deterministic position. When quantum theory is included, the determinism is replaced by probabilities that exist at any point in time and any location.

How does matter effecting the geometry of space/time demonstrate that the B theory is correct.

It isn't just that matter affects spacetime. It is also *how* it does so. So, it is possible that one observer sees event A as in the past of event B while another sees B as in the past of A. There is no universal 'past'. And that eliminates the A theory of time.

Whether it is quite the B theory is another matter. But the fact that spacetime has a geometry says that all times and locations have an existence that is objective, which is one of the key ideas in the B theory of time.

 

[Brian2]

Precisely. It was not caused because it could not be caused. it just is.



That is the strictly deterministic position. When quantum theory is included, the determinism is replaced by probabilities that exist at any point in time and any location.




It isn't just that matter affects spacetime. It is also *how* it does so. So, it is possible that one observer sees event A as in the past of event B while another sees B as in the past of A. There is no universal 'past'. And that eliminates the A theory of time.

Whether it is quite the B theory is another matter. But the fact that spacetime has a geometry says that all times and locations have an existence that is objective, which is one of the key ideas in the B theory of time.

So it is not everything moving through time and space, it is,,,,,,,,,,,,,,,,,,, everything being in another space time coordinate and being part of that space time coordinate, which has always been in existence and will always be in existence.

 

[Brian2]

And for what concern first cause arguments, I pull out B theory only when I am lazy, since it is a sudden killer of outdated cosmological arguments like Kalam. However, that is not fun. It would be like dueling with someone with a knife by using an atomic bomb. So, when I am not lazy, I rather challenge differently. Kalam, and similars, is great as a study case showing how many independent avenues, from science to simple logic, can lead to its utter destruction in just a few moves.

Ciao

- viole

Considering that most people don't know about let alone believe in a B theory of time, I don't know how it can be used in an argument about first cause with those people.
How do you defeat A theory first cause in a few moves?

 

[viole]

Considering that most people don't know about let alone believe in a B theory of time, I don't know how it can be used in an argument about first cause with those people.

Are you telling me I cannot defeat an argument posed by X, because X is ignorant, and wants to remain like that?

Well, then I agree. Actually, I cannot. i don’t need to. In the same way it would be pointless to defeat the arguments of a flat earther because it is ignorant about geometry.

How do you defeat A theory first cause in a few moves?

I would invoke the origin of the arrow of time. Ergo, the privileged direction from past to future. Without that, you cannot make sense of causality, and because of its origin, it could not have existed in the young universe. Therefore, causality is undefined at those initial states.

That would be A theory and Boltzmann. 19th century physics, basically.

ciao

- viole