Plank time is not the shortest possible duration, it is merely a unit of measurement derived from natural constants.

What is the duration of now? Just this long. That's your answer. — tim wood

Hmmm... and would that be a finite or infinite 'this'?

But am pretty sure that if you want to invoke physics as you're wont to do, then you have to take care to think in term of space-time. Not so easy. — tim wood

With spacetime, time is just another dimension so it is actually easy in spacetime - for anything to have existence, it must have non-zero duration.

The question 'what is the length/duration of now?' becomes more difficult if you consider it from a presentist (non-physics) point of view. Presentists do not regard time as a dimension. But time is still a measurable degree of freedom. So a non-zero duration of now still seems required for existence?

This greater time is referred to the time of God and how he sees the world. — RBS

Interesting. I see God as timeless rather than a creature of time (or greater time).

I am not clear though on what you think the length of now is?

And are you presentist or eternalist?

My guess is that YOUR guess on your question...will be the one you determine will best lead to, "Therefore the universe is finite." — Frank Apisa

You are correct, this is another potential example of infinity (in the small). I am a finitist, so I suspect the answer is (c) finite. I think Infinity does not exist so neither does 1/∞.

I have a model of the universe that I think may turn out to be right: it is all finite in time and space, everything is discrete. So my investigations are directed towards finding out if that model is valid. Maybe I'm wrong... time will tell I hope.

"How long is now" is just a nonsense question. — tim wood

'What is the duration of now?' if you prefer. Reading up:

"A Planck time unit is the time required for light to travel a distance of 1 Planck length in a vacuum, which is a time interval of approximately 5.39 × 10 −44 s."

https://en.wikipedia.org/wiki/Planck_time

And:

"The Planck length is sometimes misconceived as the minimum length of space-time, but this is not accepted by conventional physics, as this would require violation or modification of Lorentz symmetry"
https://en.wikipedia.org/wiki/Planck_length

So it is not a simple as just the Planck length.

With eternalism, the length/duration of now makes sense. With presentism, it is not clear. There is still a degree of freedom called time and it seems measurable. So a duration of now seems to still make sense.

Where?

So now I must accept the dogmatic proclamation that "time" did not exist before that "first cause" that you are imagining? — Frank Apisa

The logic is that everything in time forms an infinite regress with no start. The only way escape that infinite regress is a timeless first cause. Else there can be nothing. Unless you have another way?

I think you are avoiding answering this question:

Demonstrate how anything in time can exist without a first cause please.

YOUR FIRST CAUSE IS AN EXAMPLE OF SOMETHING THAT CAN EXIST WITHOUT A PRIOR CAUSE...WHICH IS WHAT YOU PROBABLY MEANT TO SAY. — Frank Apisa

Yes, let me rephrase the question:

Demonstrate how anything in time can exist without a first cause please.

That's pure dogma. You don't really belong here on a philosophy forum. Dogma is unwelcome. — S

You are illogical and closed minded. I've explained an infinite regress in enough detail that a child could get it. I give up. :(

That IS NOT the only way, Devans — Frank Apisa

Demonstrate how anything can exist without a first cause please.

Any system can be thought of as a hierarchy of cause and effect. A pool table is an example. The player breaks off and the balls bump into each other - there is a hierarchy of cause and effect with the player breaking off at the top of the hierarchy and the balls finally at rest at the bottom of the hierarchy.

What you are suggesting is a system with no first cause: this would be equivalent to balls wizzing around the pool table by themselves without the player breaking off.

Devans, the moment you say there is a "first cause"...you are saying "Not everything has a cause."

That is inescapable...and is at the heart of the flaw in your thinking on this issue. — Frank Apisa

No: everything IN TIME has a cause. The first cause is outside time so is not subject to causality.

That is the only way that anything can logically exist.

If I made a peripheral guess...it would be: "Perhaps human abilities to solve problems are being over-rated." — Frank Apisa

We would not make much progress in science or philosophy if everyone took that attitude.

Riding in a beam of light seems imponderable too but that thought experiment was very productive for Einstein. Sometimes considering things seemingly left-field can lead to ideas.

Do you think the length of now is:

a. zero
b. infinitesimal
c. finite
d. not applicable

Everything must have a cause apart from the first cause:

(first cause) -> A -> B -> C

If we take away the first cause, then A, B, C don't exist anymore.

For any object, you should be able to trace a causal history back to the first cause; if you can't, then the object does not exist.

The question is 'what (if applicable) is the length of now?'.

Its one of those questions that might lead somewhere or might not even make sense, depending on the nature of time (which no-one really understands).

You are confused. Causality works forwards rather than backwards. So you have to work from the oldest first - the more recent elements depend on the oldest element. If the oldest element is missing, more recent elements are not defined:

A (causes)-> B (causes)-> C

If you take A away, B and C go. A regress needs a first element. An infinite regress does not have a first element.

Please elaborate...

The fact nature exists and cannot have always have existed implies that something beyond nature (=supernatural) must exist.

My approach is to assume certain common sense rules/axioms constrain govern the situation surrounding the singularity. IE we don't have a guaranteed set of natural laws but certain common sense axioms should still hold:

- can't get something from nothing (excepting the zero energy universe theory)
- 2nd law of thermodynamics
- cause and effect
- No magic allowed

The above transcend the natural laws so can be used to analyse the situation and hopefully get somewhere...

If God existed amid nothingness, then both would be finite because neither would omnipresent. Two things existing independently requires both space and time. You can't just cherry pick natural laws and apply them where they fit your imaginary model of reality while removing them where they don't fit your model. — whollyrolling

We have a breakdown of natural laws at the singularity... we have to try to use common sense instead. Something must of been causally before the singularity and it is not of our spacetime. It is timeless (to avoid an infinite regress).

Good point about two things existing independently requiring space. Applies for matter. Not for pure energy though maybe? So God + energy could exist without spacetime? Or God is energy without spacetime?

It's inconsistent and pointless. — whollyrolling

Sorry you feel that way. Obviously feel free to duck out any time.

I think a key question is can space exist without time?

- Yes. Then material and God could exist in space without time. God would probably be material.
- No. Then God only exists and he is non-material (unless there is something not-God and not-material).

In our universe, space cannot exist without time:

- Does something of zero seconds long exist? No
- A 3D analogy is to have a cube length zero. It does not exist - take away one dimension and the others cease to exist

So God is timeless, space cannot exist without time, suggesting God could be 'spaceless' too?

Material exists in time and space, which is finite, but if material existed prior to all things, along with God, then both are also infinite. — whollyrolling

God (and the material if applicable) could exist in a sea of nothingness. Nothing is nothing so it does not count as infinite.

1. God wouldn't be creating something from nothing, God would be creating something from God--because there was only God. In this example, God is material and infinite. — whollyrolling

Maybe he might have to 'seed' it with something from God, but then the matter could be created from nothing:

https://en.wikipedia.org/wiki/Zero-energy_universe

Pantheism is a hard sell.

2. If material existed along with God, then God is separate from material, not omnipresent, both are finite and also infinite and God is arguably non-material. — whollyrolling

Everything would be finite - God and the material - why do you say 'both are finite and also infinite'?

BTW I thought of a funny proof that God is not omnipotent: Could God create a copy of himself?

Let's keep this going and make less sense of something that is already absurd. — whollyrolling

Not as absurd of some of the Cosmology theories for the early universe I've seen IMO.

The leading Cosmology theory, Eternal Inflation, has matter created out of nothing as per the Zero Energy Universe theory.

We know of more than one. The material, of course, and the idea - maybe capital I Idea. That is, there is that that is, and that that mind creates in itself. — tim wood

Can an idea said to be real though? Is it just electrical signals in our brains? I'm not sure an idea has independent existence as in Plato's theory of forms:

"The theory of Forms or theory of Ideas is a philosophical theory, concept, or world-view, attributed to Plato, that the physical world is not as real or true as timeless, absolute, unchangeable ideas."

https://en.wikipedia.org/wiki/Theory_of_forms

And energy and matter are different forms of the same thing, yes? As suggested in e = mc^2. — tim wood

I'm not sure if Einstein's stuff applies outside spacetime, but you might be right. The photon is the only thing close to non-material I can think of.

So we have infinite reality devoid of time and space, and then a universe is born. Where and when is it located within the infinite reality?

And what is it made from, I'm also curious about this? — whollyrolling

I am not sure. Continuing to assume the existence of a timeless God, reality would initially consist of:

1. In the beginning there was God only
or
2. In the beginning there was God and some stuff

The first option, God might create matter from nothing by exchanging it for negative gravitational energy as per the zero energy universe hypothesis. Or maybe pantheism applies in some way (a part of God becomes the universe's matter somehow).

The 2nd option is more in the spirit of the conservation of energy but does not seem as Occam's Razor as the first.

That's codswallop. Each year is defined by the previous year, to infinity. There's an infinite number of defined events. They're all defined. Every single one of them. — S

Yes but working from the other direction - there is no start - so none of the years are defined. And that is the correct direction to work from - time does not run backwards - the future does not define the past. An analogy of how it works is here:

https://thephilosophyforum.com/discussion/comment/277817

Not all regresses are in time. Logical statements form a regress in that each logical statement depends on prior statement(s) for justification.

I can't actually think of an infinite regress example that does not involve time. Not surprising really constructing anything infinite is impossible because you would never finish.

All regresses in time are similar. Time itself is a regress. If you think about a moment, it defines/causes the following moment, so it forms a regress.

The point of a regress in time is that it has a distinct order - time order. And later events depend on earlier events. So you can't just reverse the order - you lose all the semantics - the cause and effect relationship between the events.

But how does a finite regress work any differently to an infinite regress? Without a start, neither exist.

You can't number the events in reverse time order: the cue causes the white to move causes the black to move. There is a causal ordering of events - it's impossible for the black to go in the hole before the white hits it.

We have a pool table. The cue hits the white ball. The white ball hits the black ball. The black goes in the pocket.

Would the black ball go in if the cue did not hit the white?

No it would not - we have removed the first element in a time ordered regress and so the rest of the regress disappears.

So the first element (in time order) is key - it defines the whole of the rest of a regress. If it is absent as in the case of an infinite regress, then the regress does not exist.

Because the oldest item defines all the other items in the regress. For example:

{ 2016, 2017, 2018 }

If I somehow could remove the year 2016, would the years 2017 and 2018 still exist? No they would not - they are determined and defined by 2016.

So you have to start with the oldest item. 2018 does not exist; is just vapour without 2017 so you can't start at 2018.

Start at 2018. We know what that is. Then work backwards. Define 2017 as the year before 2018. And 2016 as the year before 2017. A neat recursive definition. — Banno

But you cannot start in 2018 - 2018 does not exist until 2017 has happened. 2017 defines 2018. You have to choose the start as the oldest item - and there is no oldest item in an infinite regress.

Because there is no start, none of the years are defined.

Look:

{ ..., 2016, 2017, 2018 }

It has no start, that's what the ... mean. If it had a start it would be a finite regress.

It does not matter which order you write it - it is the temporal order that matters - and 2017 comes before 2018 - and it has no temporal start.

2017 comes before 2018.

I must say that bears well for eternal return, in the metaphysics sense. And I am a lover of fate, so I'm all for it. — Merkwurdichliebe

I have a suspicion that eternal return could be true but for a different reason. I think eternalism maybe true and time could be circular. So we could all end up living the same lives again and again.

But it offers us no help concerning whether or not multiple Devans99s can exist sinultaneous across space and time, it only suggest you exist again in every detail. And if that is the case how important is every moment, how precious is the instant? — Merkwurdichliebe

I think it would be an identical me but a different instance of me. So not an answer to eternal life in the way that circular time would be.

No an infinite regress in time looks like this:

{ ..., 2016, 2017, 2018 }

The ... indicates that it has no start.

But the key point is an infinite regress has no start. If there is no starting element, then the element next to the start is undefined and so on for all the others.

An infinite regress is like a house without a foundation.

I am still formulating my thoughts as to how best to dismiss infinite regresses.

That long proof needs some more work...

I agree that the universe is finite. But if it was infinite, the this applies time wise:

https://en.wikipedia.org/wiki/Poincaré_recurrence_theorem

But you can think of two blocks of space as equivalent to 'now' and 'then' - space is equivalent to spacetime as far as the Poincaré recurrence theorem.

No I am saying there is a property of all regresses called 'number of elements' and it is an integer property.

You cannot set an integer property to a non-integer value.

But if its infinite, it can't be a regress - a regress has an integer number of events in it.

Or if you prefer, the first event defines the second, the second the third, and so on down the chain. If you have no first event, the whole of the rest of the chain must be undefined.

Infinite regresses cannot exist.

No the number of events in an infinite regress is an integer. 1, 2, 3 ... is how we count events with integers. Infinity is not an integer. Its impossible to count to infinity. So it cannot be the number of events.

But it's not an integer. So it can't be the number of events in an infinite regress - that takes an integer value.