YAY! I'm the first to post here!

What's this all about?

[Tenspace]

It's about you, Archy. Didn't you get the memo?

In my opinion, we already have too many topics. If anything, we should have cut it down a bit not added another one.

[Tenspace]

The purpose was to add a specific topic for discussion of the Sciences, as requested by many members here: http://ravingatheist.com/forum/viewt...hp?id=3267&p=1

Sweet!

Anyone up for some Cosmology? Tim posted a while back on the no-boundary condition, but the most I've read about it was from before the discovery of the accelerating universe. It seems to me like the finite-but-boundless universe theory is no longer consistent, but I don't pretend to know much more about it.

Discuss!

[Tenspace]

whoneedscience wrote

Sweet!

Anyone up for some Cosmology? Tim posted a while back on the no-boundary condition, but the most I've read about it was from before the discovery of the accelerating universe. It seems to me like the finite-but-boundless universe theory is no longer consistent, but I don't pretend to know much more about it.

Discuss!

I'm in the "There is no time" camp, therefore I cannot subscribe to anything that delineates a condition based on rods and clocks.

There, that should get things started. ;)

[anthonyjfuchs]

Tenspace wrote

I'm in the "There is no time" camp, therefore I cannot subscribe to anything that delineates a condition based on rods and clocks.

I can't count all the early-morning conversations I had in college trying to convince people that the notion of "time" is just a human invention. Trying to explain that there is no such thing as an "hour" or a "week" that exists in reality.

Everything we think of as "time" is based on nothing more than an observable natural phenomena:

One second = 9,192,631,770 vibrations of a Caesium-133 isotope (since the minute and the hour are based solely upon the second, they are equally fabricated)
One day = originally sunrise to sunrise
One month = originally one lunar cycle
One year = originally summer solstice to summer solstice

The only real aspect of time that I've noticed is the notion of the past and the future, but that's really nothing more than a psychological division between things that have happened and things that will/might happen. When people invent constructs like timelines, they create the illusory perception that we somehow "move forward" in time. But really it's just things happening that creates a linear narrative of memory.

That's why time travel, while mathematically possible, can never happen. The past and future do not exist as places to which one can go in the same way that one can go to Rome or Liverpool. The past, effectively, does not exist at all; we know that certain things happened because photographs and documents exist now that can be scientifically shown to represent authentic historical events, but those events themselves are irretrievably gone.

I've always just thought of "time" as a way to ensure that anyone who needs to be somewhere gets there when they're supposed to.

Tenspace wrote

I'm in the "There is no time" camp, therefore I cannot subscribe to anything that delineates a condition based on rods and clocks.

I know you've mentioned that before, but how do you deal with time dilation? Is it not at least convenient to see time as a dimension when considering supermassive objects or the need for GPS satellites to correct for relativistic effects? I could understand dismissing the concept if it were constant, but relativity seems to throw a rather large wrench in.

[Choobus]

whoneedscience wrote

I know you've mentioned that before, but how do you deal with time dilation? Is it not at least convenient to see time as a dimension when considering supermassive objects or the need for GPS satellites to correct for relativistic effects? I could understand dismissing the concept if it were constant, but relativity seems to throw a rather large wrench in.

no it doesn't becvause time dilation (and associated effects) only stretch the relative timelike interval between events a little bit, and they are strictly confined to a light cone that cannot have any causality effects, which means that relativity, while making the idea more interesting, does not materially affect the proposition.

(by causalioty effects I mean that causality is maintained. No effects preceeding causes).

[Rhinoqulous]

Isn't Time Dilation evidence that time is a dimension of the physical universe? If we can effect the speed of an object through dimension t, it seems like we're actually interacting with a physical construct of the universe, and not just some abstract a priori notion of convenience (but again, I'm no scientist, so I'm probably wrong :P).

[Choobus]

Rhinoqulous wrote

Isn't Time Dilation evidence that time is a dimension of the physical universe? If we can effect the speed of an object through dimension t, it seems like we're actually interacting with a physical construct of the universe, and not just some abstract a priori notion of convenience (but again, I'm no scientist, so I'm probably wrong :P).

no

[Rhinoqulous]

Uhm, could you be more specific?

[Choobus]

no

[Rhinoqulous]

Choobus wrote

no

:mad:

[anthonyjfuchs]

Rhinoqulous wrote

Isn't Time Dilation evidence that time is a dimension of the physical universe?

Ehhhhhhh...sorta?

A second is measured as a given number of vibrations of a given isotope; if moving that isotope at one-tenth the speed of light changes the vibration frequency (whereby one could say that the second has become longer or shorter), does that really change the second?

Or, conversely, does calling a given number of vibrations of a given isotope a "second" make a "second" any more a tangible thing the way that a rock or a blade of grass is a real thing? The vibrations are tangible; calling 9-billion of them (and change) a "second" is as arbitrary as finding a heretofore unknown species of bird in the rainforest and calling it a "gringleblatt." It's just the word we assign to the natural phenomenon.

The fact that physical changes to the basis of our time-measurement standards can change those measurements -- speed causing a second to slow down -- to me at least, indicates that the "time" we're measuring isn't anymore than our own arbitrary construct.