what is time?

Originally posted by eatmybishop
if we could eradicate human perception of time (minutes, days, years etc) does time really exist?

put it another way, is the universe in a state of no past or future yet at the same time everchanging?

The word 'now' does not have a past, or future; however, time is
the passage of all things through the filter of 'now'; what was has
gone through, what is, is now, and what is to come will go through
'now' and move into the past. 🙂
Kelly

Well, time would exist without human beings.
Time as we perceive it, would not.

The distinction being: humans perceive time as from going from point A (say birth) to point B (say death).

Time, however, is a dimension.
It's fine and dandy to suggest meeting up in the 3D universe, say Central Station in Rotterdam, but if you don't agree a "time" then you've got very little chance of actually meeting up.
So, you could (and should) add time to the list of dimensions.

Now, every dimension is there. It was there way back then and it will be there way over then as well. So, say you look at 3D as a grid. The grid is there, was there and will be there. So will time.
That time, say 12:00 midday on Saturday 12th of October in 20xx in our perception has either come, went or is there right now.
HOWEVER... that time (12:00 on the Saturday 12th of October in 20xx) is always there.

To simplify it: You are being born at this exact moment in time and you're dying at this exact moment in time and you're reading this in this exact moment in time. Just somewhere else on the total grid.
You just don't perceive it that way.

A friend, who's a quantum gravity researcher (who tells me he's trying to disprove black-holes, but appears to me just to spend a lot of time drinking cheap vodka) says you can prove time as a dimension with scientific mathematics.

Well, that's what I think he was saying. It looked like gobbly gook to me...

Another way to perceive time is to download "Time" by Tom Waits and just bloody well enjoy it.

Everyone should read the June 2008 Scientific American, titled 'Why does time always move forward?'.
The gist of it is the universe sets up the arrow of time, going from less entropy to more entropy, less entropic during the opening moments of the big bang to our 'middle entropy' era of today to a much higher entropy in the far future.
Scientists have no clue (almost no clue, anyway), as to why that is so.
The gist of the article is there must have been a bigger universe where our universe came from to even things out, entropywise, so there can be universes that start out with maximum entropy and wind down to little entropy, just the opposite of ours, that is to say, time running backwards in that universe cancels out our forward running time so entropy as a whole is evened out in the larger universe that is on the other side of the big bang that started our universe. Of course this is just a conjecture at this point by the authors of the article but it makes sense to me. I have always thought there had to be a 'before' to the big bang, where our universe popped out like a pimple from a larger universe and there probably is an infinite number of such universes, the conjecture being in half of them time runs backwards which balances the entropy equation. Take a look at this blog, cosmicvariance.com where he talks about this issue.

Originally posted by sonhouse
Everyone should read the June 2008 Scientific American, titled 'Why does time always move forward?'.
The gist of it is the universe sets up the arrow of time, going from less entropy to more entropy, less entropic during the opening moments of the big bang to our 'middle entropy' era of today to a much higher entropy in the far future.
Scientists have n py equation. Take a look at this blog, cosmicvariance.com where he talks about this issue.

but you could say there has to be a time in the future when are intelligence is so advance we could alter time...

I was so busy reading this post that I ended up late 🙁

The irony was not lost on me 🙂

how do we know that anything exists? Yogi Berra, that great American wise guy, said it best: you can observe a lot just by watching.

What he forgot to mention is that once we do observe, we draw conclusions and make pronouncements about what we saw.

It is a lot like language: do words refer to objects that have some sort of existence objectively outside of the boundaries of the usage of the words themselves? I don't think so.

A chair isn't a chair because it has the "essence" of a chair; or because it is, in "objective reality" a chair. No, it is a chair because we agree that when we use the word chair, that's what we are referring to, that's what the word means. That is also how we "know" why ceilings are above us and floors, usually speaking, are beneath us.

So the word "time" and the concepts most of us accept about how to use that word appropriately help us to make sense of the world. that doesn't prove anything, it is just a way of dealing with what we think we know now.

But, our observations of the world are an acceptable scientific reason for concluding that time exists. Science cannot prove a thing, and while some folks appear to believe that some scientific theories are absolutely proven and true, and we can then rely on these theories to prove even more things about the world, that's not such a good line of thinking, nor is it the way real science works.

My father was a research scientist. I work for a government agency the basis of which is its scientific expertise and judgment regarding chemicals, risk, and human health, among other things.

I've learned from both my old man and my work that science is based on observation, not theory.

Theory is a tool by which we can make sense of our observations. The process of science begins with measurement. We can measure time down to the smallest fraction of which we presently have the technology to conceive.

I can get water sampled and detect chemicals that exist in any given volume in quantities no greater than 1 part per billion, sometimes even less.

I don't think anyone here has decided time does not exist, as a matter of "objective" fact, or some such assertion. If so, it would be fantasy or religion.

If anyone really thought that there is only one time or one idea of time, I'd have to wish them good luck with that.

see this NASA website for a lot of good answers to the basic questions about relativity, curved space time, velocity, acceleration, time dilation, and so on:

http://imagine.gsfc.nasa.gov/docs/ask_astro/ask_an_astronomer.html

Scriabin - That's the same answer as in the laws of nature thread. :p

Is time a physical thing that can be seen, touched, felt so on? Or is it a concept made up cause stuff happens and we observe them. I'd prefer the latter, but i won't say that I'm right.

The point about entropy is kind of interesting, as I like the idea that stuff is logical. And that stuff tries to retain or create equilibrium seems logical to me. However if this proves time either way I'd be hesitant to say.

Just like most else Time is made up by us. That stuff happens, and we can agree they happen the same order though, is not.

Originally posted by Tera
Scriabin - That's the same answer as in the laws of nature thread. :p

Is time a physical thing that can be seen, touched, felt so on? Or is it a concept made up cause stuff happens and we observe them. I'd prefer the latter, but i won't say that I'm right.

The point about entropy is kind of interesting, as I like the idea that stuff is logical. And that s ...[text shortened]... e up by us. That stuff happens, and we can agree they happen the same order though, is not.

It is the same answer because it is the same question.It is an answer that logically follows from the terms of the question in both threads. It is also an answer true in all cases. It is a logically valid answer.

As for choosing to understand the universe and your own existence as a matter of logic, well, good luck with that.

I minored in philosophy taught by by a logician, not a theologian. Logic deals with the principles and criteria of validity of inference and demonstration: the science of the formal principles of reasoning.

It has little application or value in terms of observation or describing and explaining natural phenomena. It isn't suited to that. Simply because what you come up with logically may be a valid sentence has nothing to do with whether it has reference to the world outside the medium in which you choose to write out your equations. In other words, just because an argument establishes a valid proposition does not make it true.

There are many formal systems of logic, and Sentential Logic is one of the simplest. It is also known as "Propositional Logic". When people study formal logic this is usually the first thing that they study. Other more complicated systems include for example predicate logic (PL), and modal logic.

A system of logic is a set of rules that tell us how to make use of special symbols to construct sentences and do proofs.

It is elementary logic that to prove a proposition, you must come up with a convincing demonstration that some statement, reduced to its mathematical elements, is necessarily true, within the accepted standards of the field.

A proof is a logically deduced argument, not an empirical one. That is, the proof must demonstrate that a proposition is true in all cases to which it applies, without a single exception. An unproven proposition believed or strongly suspected to be true is known as a conjecture.

Thus, if you start from a premise that is not true, you cannot prove it so.

So, before you assume the truth of your assumptions a priori, then tell me you prefer reality to conform to your notion of logic, forgive me if I allow myself a chuckle or two.

I was taught propositional logic, and introduced to set theory, model theory, recursion theory, proof theory and constructive mathematics. These areas share basic results on logic, particularly first-order logic, and definability.

There are many logics besides first-order logic, however.

See http://euclid.trentu.ca/math/sb/pcml/

This is a free online text on mathematical logic.

If you are going to throw around the concept of logic, you might want to know something about that to which you refer.

Finally, it would be helpful if your final sentences in a post were coherent.

Originally posted by Tera
Just like most else Time is made up by us.

No, Time is not a human invention. Time existed before man.

Originally posted by FabianFnas
No, Time is not a human invention. Time existed before man.

Maybe the stuff that happens which we take as "proof" or answer to our notion of time. But the notion that we think about time as something specific and refer to it in more a sense than just, "this is now, that was then and soon is tomorrow". That concept is designed by humans, and is partly a product of language and communication.

However it may be so that time is just that. And thus we haven't created more than the 'label' -so to speak- for it.

Originally posted by Scriabin
As for choosing to understand the universe and your own existence as a matter of logic, well, good luck with that.
...
So, before you assume the truth of your assumptions a priori, then tell me you prefer reality to conform to your notion of logic, forgive me if I allow myself a chuckle or two.
...
Finally, it would be helpful if your final sentences in a post were coherent.

First off, If your referring to me choosing to understand existence and that as logic that that wasn't what I was trying to say.

The next paragraph I don't really understand, did you mean without the "a priori"? Anyway I will try answering. "If you assume you are right then jada jada..?" - Why would I try a answer if I thought I was wrong? "Then tell me you prefer reality to shape as you think is most logical." - I like when things make sense, if stuff don't then I may not understand it or they are wrong or both or something else whatever.

As to answer your entire post. Logic makes bad science. Sure I never said logic would, however I still like when stuff is logical. And I like to understand something and most often once I do, it's kinda logical. I may have this the wrong way.

And about thinking your right, sometimes it just makes for better discussions if you take the opposing view sometimes, whatever your opinions are.

And about the last quote. I don't understand how their incoherent, but I'll try using a more coherence next time. Sorry. 🙂

ps. Also thanks for the personal info. I now know lots about you, Thanks.