Can causality exist without time?

[Belz...]

Or:

There would be no "events."

Even better

 

[Modified]

Why? The events exist eh?

But can't be causally related, because they all have space-like separation. Of course, as others have pointed out, without time there are no events anyway.

 

[69dodge]

Has anyone definitely answered the question yet? ie can causality operate independent of time (I think it can although its very counter intuitive).

I guess I don't know what you mean by "causality". Given a pair of events, how do you decide whether one is the cause of the other? It's hard to give a precise definition, but can you give some examples?

I figure that most people, even if they couldn't say exactly what they mean by "cause", would not hesitate to say that a later event couldn't possibly cause an earlier one. So, time certainly seems to be involved in causality.

 

[orange31]

Has anyone definitely answered the question yet? ie can causality operate independent of time..

Well, a beam of light from your perspective has had it's time stopped.
Yet the beam of light can still cause a photoelectric effect, or a sunburn, etc on another planet- 'causality' - so I'd say the answer is 'yes'.

 

[The Man]

Has anyone definitely answered the question yet? ie can causality operate independent of time (I think it can although its very counter intuitive). I apologize for not reading all the replies in their entirety.

Yes, the question has been answered, causality has no meaning without time. If you want to assert causality without time you’re going to run into problems. However, the reverse is different, time can exist without causality. Time can be measured by changes, that those changes may not be causally related to past times makes no difference in the ability to observe such changes. Fortunately, we currently live in a universe where the future is (to some probabilistic degree) related to the past. As by some of our current understanding that causal relationship ends sometime in the past. Does this mean that time ends? Not as far as we can tell, all we can say is that from our current understanding we may not be able to find any definitive causal extent past that time or the big bang singularity.

 

[RevDisturba]

Well, a beam of light from your perspective has had it's time stopped.
Yet the beam of light can still cause a photoelectric effect, or a sunburn, etc on another planet- 'causality' - so I'd say the answer is 'yes'.

Yes I have to agree with you. You used the PE effect, we could use gravity from a black hole where in theory time stops. The man (above) is confusing the concept (the arrow of time with time). The events exist with or without time. They could theoretically be accessed from an observer outside time. So I think that causality can and does exist independent of time. Remember what Kurt Gödel proved in conjunction with his walking buddy at Princeton (Albert Einstein), which was that time did not exist. If time doesn’t exist, we see that causality does everyday. I will include the book where I got the Gem about time from one of my heroes Kurt Gödel. it’s a fantastic small book, I would highly recommend it to anyone interested in such things.

Yes I have to agree with you. The man (above) is confusing the concept (the arrow of time with time). The events exist with or without time. They could theoretically be accessed from an observer outside time. So I think that causality can and does exist independent of time. Remember what Kurt Gödel proved in conjunction with his walking buddy at Princeton (Albert Einstein), which was that time did not exist. If time doesn’t exist, we see that causality does everyday. I will include the book where I got the Gem about time from one of my heroes Kurt Gödel. it’s a fantastic small book, I would highly recommend it to anyone interested in such things.

A World Without Time : The Forgotten Legacy Of Godel And Einstein ...
He added a philosophical argument that demonstrates, by Goedel's lights, that as a consequence, time does not exist in our world either. If Goedel is right, ...
- 40k

; {>

 

[RevDisturba]

But can't be causally related, because they all have space-like separation. Of course, as others have pointed out, without time there are no events anyway.

If there are no events independent of time how can a (the 'interior') black hole exist and effect the outside universe ie in quantum entanglement and other processes such as Bekenstein-Hawking radiation?

If one of a pair of virtual particle falls into the event horizon and the other escapes as per Hawking radiation the particle in the hole should be connected via quantum entanglement outside of the hole, correct?

; {>

 

[RevDisturba]

As by some of our current understanding that causal relationship ends sometime in the past. Does this mean that time ends?

I don't understand you. We know that time begin to exist a fraction of a nano second after the big bang. So before time zero there was no time. However this is where things get interesting in a first cause cosmological argument and is the reason for the question.

If everything that begins to exist has a cause for its existence that means that the universe had a 'cause' to allow it to begin to exist.

Ahhh' yes! The rub! The 'cause' (for the universe to begin to exist) according to deductive logic existed 'before' time was created in the big bang! So hence the question!)

; {?

 

[martu]

I don't understand you. We know that time begin to exist a fraction of a nano second after the big bang. So before time zero there was no time. However this is where things get interesting in a first cause cosmological argument and is the reason for the question.

If everything that begins to exist has a cause for its existence that means that the universe had a 'cause' to allow it to begin to exist.

Ahhh' yes! The rub! The 'cause' (for the universe to begin to exist) according to deductive logic existed 'before' time was created in the big bang! So hence the question!)

; {?

No time began at t=0 the Big Bang and not a fraction after.

Your second paragraph assumes it's conclusion.

 

[Mashuna]

I don't understand you. We know that time begin to exist a fraction of a nano second after the big bang. So before time zero there was no time.

I don't know that this is an accurate inference you're drawing here. We know that our current model shows time beginning after the big bang. The current model breaks down at t=0 and has no information about what was going on before the big bang.

At least, that's my layman's understanding of it.

 

[martu]

If there are no events independent of time how can a (the 'interior') black hole exist and effect the outside universe ie in quantum entanglement and other processes such as Bekenstein-Hawking radiation?

If one of a pair of virtual particle falls into the event horizon and the other escapes as per Hawking radiation the particle in the hole should be connected via quantum entanglement outside of the hole, correct?

; {>

Do the maths, specifically Einstein’s General Relativity equations.

As to your second paragraph I do not know and I do not know how we could know as we can’t interact with the particle ‘lost’ to the black hole.

 

[sol invictus]

If there are no events independent of time how can a (the 'interior') black hole exist and effect the outside universe ie in quantum entanglement and other processes such as Bekenstein-Hawking radiation?

The interior has a perfectly good time variable. That stuff about time stopping is wrong. Moreover, the interior of a black hole cannot and does not affect the outside.

If one of a pair of virtual particle falls into the event horizon and the other escapes as per Hawking radiation the particle in the hole should be connected via quantum entanglement outside of the hole, correct?

That's the wrong way to think about it - but the reason is not relevant to this discussion. Nothing goes wrong with time at the horizon or in the interior, and there's a perfectly sensible causal structure inside (it's just that time ends at the singularity - or rather, the equations break down there, just as they do near the big bang).

I don't understand you. We know that time begin to exist a fraction of a nano second after the big bang.

No we don't.

So before time zero there was no time. However this is where things get interesting in a first cause cosmological argument and is the reason for the question.

If everything that begins to exist has a cause for its existence that means that the universe had a 'cause' to allow it to begin to exist.

Ahhh' yes! The rub! The 'cause' (for the universe to begin to exist) according to deductive logic existed 'before' time was created in the big bang! So hence the question!)

If you would bother to read the thread, that point was extensively discussed. Even if time did begin at t=0 that does not imply that there was a first cause. All you have to do is pick the set t>0, rather than t>=0, and there is no first moment. One can pick a time variable - one which might be better suited to describing physics near the singularity - in which t=0 gets mapped to t=-infinity.

 

[The Man]

I don't understand you. We know that time begin to exist a fraction of a nano second after the big bang. So before time zero there was no time. However this is where things get interesting in a first cause cosmological argument and is the reason for the question.

As Mashuna said and I alluded to before, our understanding of specifically causality breaks down at T = 0 or at some T > 0, depending on which consideration you focus on, relativistic or quantum. The mere ascription of T = 0 infers that time exists at T= 0. We just have no verifiable models that allow us to assert time or casualty before T = 0. This lack of understanding certainly does not demonstrate a lack of time or casualty before T = 0. We model the universe based on our understanding not by our lack of understanding.

If everything that begins to exist has a cause for its existence that means that the universe had a 'cause' to allow it to begin to exist.

Ahhh' yes! The rub! The 'cause' (for the universe to begin to exist) according to deductive logic existed 'before' time was created in the big bang! So hence the question!)

; {?

Time does not require or infer causality. In a completely random universe there would be no casualty, so any measurement of time in that universe would be, well, random. Not inconceivable but just not a very useful universe and fortunately one that we do not find ourselves in at this time.

 

[The Man]

The interior has a perfectly good time variable. That stuff about time stopping is wrong. Moreover, the interior of a black hole cannot and does not affect the outside.

That brings up a good point Sol, so the interior of the black hole is casually related to the exterior (stuff falling through the event horizon) but the exterior is not causally related to the interior (nothing escapes the event horizon). Would that be a fair statement based on our current understanding?

 

[sol invictus]

That brings up a good point Sol, so the interior of the black hole is casually related to the exterior (stuff falling through the event horizon) but the exterior is not causally related to the interior (nothing escapes the event horizon). Would that be a fair statement based on our current understanding?

That's the case in classical gravity.

The situation in quantum gravity is extremely subtle, but the best current understanding is that the region outside the horizon is actually causally complete - no information is ever lost into the hole, because before it crosses the horizon it is vaporized by Hawking radiation and eventually radiated away (just like the smoke and light from something burning).

 

[The Man]

Yes I have to agree with you. The man (above) is confusing the concept (the arrow of time with time). The events exist with or without time. They could theoretically be accessed from an observer outside time. So I think that causality can and does exist independent of time. Remember what Kurt Gödel proved in conjunction with his walking buddy at Princeton (Albert Einstein), which was that time did not exist. If time doesn’t exist, we see that causality does everyday. I will include the book where I got the Gem about time from one of my heroes Kurt Gödel. it’s a fantastic small book, I would highly recommend it to anyone interested in such things.

I must have missed something. What concept am I confusing, particularly considering you’re making a similar point that time can exist without causality? However, if you want to assert casualty without time you must have a very unique definition of casualty.

 

[The Man]

That's the case in classical gravity.

The situation in quantum gravity is extremely subtle, but the best current understanding is that the region outside the horizon is actually causally complete - no information is ever lost into the hole, because before it crosses the horizon it is vaporized by Hawking radiation and eventually radiated away (just like the smoke and light from something burning).

Right, I forgot about the loss of information approaching event horizon, thanks.

 

[Perpetual Student]

If you would bother to read the thread, that point was extensively discussed. Even if time did begin at t=0 that does not imply that there was a first cause. All you have to do is pick the set t>0, rather than t>=0, and there is no first moment. One can pick a time variable - one which might be better suited to describing physics near the singularity - in which t=0 gets mapped to t=-infinity.

Looks like the "time" version of Zeno's paradox!

 

[The Man]

I think some of the confusion of this thread may be the result of what the “0” in T = 0 represents. As a measurement a zero value denotes a lack of whatever you are trying to measure. However, as an ordinate position zero is just a location on a line or within a set. The latter is the case in this consideration. We could just as easily ascribe “now” as our zero ordinate position for time. From our perspective it is always “now” so we would not move along that timeline, events in the past just get further away from us as events in the future move closer. So as an ordinate position zero does not represent a lack of time as a zero measurement would.

 

[The Man]

RevDisturba, is it the general interpretation of causality (past resulting in future) being related to the arrow of time that has you thinking I am confusing the concept? There are considerations that define causality as being time symmetrical, involving both retarded (forward time) and advanced (reverse time) waves. They are Wheeler Feynman Absorber Theory and The Transactional Interpretation of Quantum Mechanics. However, they do have their own problems involving free emission and self interaction.