Demigod Forums
LOL ... i have to mention this...
i just saw, some guy posted (on youtube) that the universe has an age of 14 billions years. Okay, i know jack shit about this topic but how could anyone know when the universe came about. Unless he was joking, but i doubt it coz he had all these other statistics.
i LOL'ed hard at this.
(infinity , infinity)
Even prior to the big bang all matter was accounted for. In energy. The universe has no end. You know the saying "everything that has a beginning must have an end?" well there is no end here...no beginning either. The universe just is. It always was. Constantly changes form from energy to matter and back and forth. Big bangs happen on a universal time scale all the time . Time is relative to light anyways. Everytime we look at the sun we see it in its 8 minutes ago form. Time is different here than it is many light years from here. The edge of the uinerse as we know it is simply a light barrier, the fastest and furthest ligh has reached.
This kind of stuff makes my head almost explode... I thought the universe was the whole thing.
u·ni·verse [yoo-nuh-vurs] –noun
1. the totality of known or supposed objects and phenomena throughout space; the cosmos; macrocosm. (source: dictionary.com)
Isn't it supposed to burn out eventually?
I agree, once we find "another universe" they no longer are a universe each but one universe together.
What happens when things burn? They convert to the state of energy that is heat. The universe is constantly moving towards chaos as they say. At some point it all will be energy again in different forms.
When they are talking about the age of the universe they aren't talking about space or everything in it. They are just talking about the time since the big bang.
I'm going to say it one more time - we don't know about the conditions 'before' the big bang. We don't know if all energy was accounted for 'prior' to the big bang (although again, if the big bang created both time and space, then is there such a thing as 'before the big bang'?). At this point in time, any speculation about 'before the big bang' is purely philosophical. We might expect that all matter/energy was accounted for, but it needn't be the case. If there was a beginning to time (maybe there was, maybe there wasn't), then energy could, philosophically speaking, have been created from nothing. This is because conservation laws are only applicable under the existence of time. But I can't stress enough that, even though some physical principles and observations may be referenced, everything about this stage of our universe is entirely and purely speculative and philosophical.
And we certainly don't know that big bangs happen on a universal time scale all the time. It's true that up until about a decade or two ago, physicists thought that a repeating cycle of Big Bang -> Big Crunch -> Big Bang -> Big Crunch ad infinitum was a likely scenario, but that theory was fallen almost completely out of favor in light of new cosmological observations.
To be more specific, time is relative to reference frame. The statement 'time is relative to light' actually opens up a can of worms. For one, if you could, theoretically speaking, hitch a ride on a beam of light, you would experience the entirety of time in a single, infinitesimal moment. The same is true of any other massless particl, like gluons, and also gravitons (if they exist - we've never observed or measured gravitons or gravitational waves, but we think they should exist). It's true that time is relative and passes at different rates in different places and velocities, but that relatively is not free-form. It follows a very strict set of rules, and we can still speak about things like 'the age of the universe' by determining standard measures of time. The trick here is that that standard measure would be different in different locations/speeds in the same way that time itself is, allowing for a perfect 'translation' if you will.
Edit: TheOneX explained it much more simply and better than i did, so... yeah.
The current concensus is that, if our observations are correct, then the universe is likely on a one-way ticket to 'death'. The manner of death, though, is debatable.
It might undergo what's called 'heat-death', where the universe ends up in a thermodynamic equilibrium of maximum entropy. Essentially, there is no free energy left available to.. do.. anything. Perfectly stable particles, if they exist, would be stretched evenly but infinitely thinly.
Another potential death scenario is called the Big Rip (which I think is kind of exciting :P). Basically, the idea is that in a dark energy dominated universe (which we think ours currently is, and will continue to be - though it didn't used to be :P), the observable universe actually shrinks with time. This is because the expansion of the universe isn't just matter and all moving away from each other, but spacetime itself actually 'stretches'. Once the observable universe becomes smaller than any particular structure (whether that's a galaxy cluster, a galaxy, a star, a planet, an atom, a nucleus, a nucleon, ...), then that structure will be ripped apart because there can be no interaction between its farthest parts. The observable universe at any given point would shrink to nothing, and the universe would essentially cease to exist.
Good info. guy above deserves a +1 Karma. However, as I agree, you have not mentioned any end to the universe. Even a dark energy state is not the end. The end of the universe would require nothingness anywhere and everywhere...a term I am uncomforble with. I am a radiologist and not a astrologist but hey, I love this stuff. It is all theory though. Kind of like the parralel universes theory. We can only tell how far the universe has strechted by light so far is with red/green/blue light testing. I stick with the fact though that matter/energy can not be created and destroyed...it only goes through transformations. This has continued from infinity and will continue to infinity. Timespace is a tough concept to comprehand, I thought it was easy but when I read about it...I found out many challenging things.
Before the big bang could be many possiblilities...but they are something and not nothing. This something is already a universe in my opinion. It at least has the value for the universe that we know of now.
I definitly stick with what I said "that time is relative to light". The speed of light is our standard of time. If you would have to convert to our measurement as you say in other galaxies for example that would only prove me right, because it is relative to your location. Time has a relationship with the speed of light. If you were to travel the speed of light is not a proper "what if" statement...you logically can't..any mass traveling at the speed of light would have infinite mass.
It is all theory - more than that, most of what we've been talking about lately has been more philosophical theory, rather than scientific theory. But you are right - none of the possible scenarios that have been thought of include the matter and energy of the universe vanishing. But then again, how could they? The scenarios we've developed rely on the physical laws we know of - but the physical laws we know aren't capable of predicting a scenario in which that occurs. It would either violate energy conservation, or somehow predict the end of time and space itself (which our theories are inherently incapable of doing). So yes, as far as we know that won't happen, but we also don't know that it won't (or couldn't) occur (our understanding of the universe is incomplete). It's weird, and bizarre, and I'm not particularly comfortable with it either - but our comfort is irrelevant 
Hell, Einstein was as uncomfortable as you can get about quantum physics, and yet all the evidence points to the world not caring about his feelings.
But my point is that there may not be such a thing as 'before the big bang.' "Before the big bang could be many possibilities" is an understatement - a more correct statement would be, "Before the big bang could be anything, including nothing, not even time itself." Again, it's bizarre and strange and difficult to accept and, at least to me, impossible to really imagine or understand - but just like the universe doesn't care about our feelings, what came before, what might come after, or what might be outside the universe wouldn't care whether we can imagine it or not.
You're right that we can't logically travel at the speed of light, but light can. Light experiences all time (even if its infinite) in a single instant. Whether we can experience that a well is not really relevant. But more importantly, the speed of light isn't our standard time. Our standard time is not the speed of light (a speed can't be used as a 'standard time' - although a combination of speed and distance could be). We have a few standard times, actually. The two most prominent civilian ones now I think are Universal Time and International Atomic Time. Light is used as a means to measure the former, but it itself is not the standard. To go even farther, the SI Second (SI = Le Système International d'Unités) is defined by the atomic resonance frequency of caesium.
Haha ofcourse the universe doesn't care what we think or feel. I didn't mean it like that. I just logically can't comprehand nothingness when it comes to the universe, I can only comprehand nothingness when it comes to consciousness. Even space is not just empty space. Our conscious mind has a beginning and an end. The matter/energy/universe around us logically doesn't. It just is and was. That is my theory if anything than. I think the big bang wasn't the beginning of the universe but rather just an event however it did transfrom it into what we see it as today. It could have been in a small atomic high energy state. Just speculation. Somehow I don't see the universe escaping the bounds of logic, nothing has yet. It may seem weird at first once we get more answeres but it will make logical sense as we dive deeper into them. However if you start talking about beginning of the universe you might leave room open for hokie pokey supreme beings and that is when I leave the room.
Our defintions of time are so premitive. Half of it is still based on sun going up and down and earth revolving around the sun. All Mayan and Egyptian techniques which aren't worth all that much when trying to really debate the idea of time. Honestly the only way time exists is when events are spread out. The interval between these events are the units of time. Light is weightless which is why it can travel exactly at the instant of time. All events happen instantly relative to the speed of light. We are going much slower, our events take "time" One second is just a SI unit of measrement. In realtiy it is nothing but a value we chose for the speed that we are moving at through time. I have never heard a second be defined as a atomic resonance frequency of caesium, I have to look that up.
I don't know everything but this seems the most logical to me. Specially when I take everything Eienstien and other great minds have put forward into account. I can't even begin to explain how light bends space, I don't know, my ideas could be all together wrong simply because I can't understand this.
Ah, but logic is based on what we know. It's based on rules of what is and isn't possible. We know so little about the first moments of our universe (ie, after the big bang), and even less about what might have come 'before' it (if anything). This means that we can make all the logical arguments in the world, but that logic will be based on speculation. It's speculation based on what we are familiar with, but nonetheless it may very well not apply to the big bang. I agree with you - I can't comprehend the concept of 'nothingness' in this sense - I don't think anyone can. But again, an open mind means not writing off the unimaginable
You're wrong that Mayan and Egyptian techniques aren't worth much when talking about time. Yes, their methods weren't as precise as our methods today, but that is how science progresses - from less accurate to more accurate. I could define a standard measure of time to be the average period between two of my heartbeats at rest. If I measure time with it standing on Earth, then get on a spaceship and fly to Alpha Centauri at close to the speed of light and measure time using the same method, I will have a fairly accurate measure of time for both situations. And as long as I have all the data corresponding to my space flight, I would be able to accurately compare both time periods. Likewise, if I decide to use the rotation of Earth as a standard measure of time, I could do the same thing (assuming I have the tools on the spaceship to continue observing the Earth). The accuracy of your standard measure of time only depends on its consistency. The rotation of the Earth is slowing down, and so to maintain an accurate measure of time we have to compensate for it; and that is why the scientific definition of a second is defined using a much more consistent measure. To quote from wikipedia:
"The second is the duration of 9 192 631 770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom."
And, I also have to point out that the issues with measuring time are identical to the issues with measuring space. Time runs differently in different reference frames, but space compensates. If you know how to convert between the time in two different reference frames, you can figure out how to convert between spatial measurements without having to make any observations or anything, and vice versa. In relativity, there is something called the Invariant Interval. Time and space both contribute to it, and the Invariant Interval is constant in all reference frames. It is constant because even though time and space change with reference frame, they change in complimentary ways.
[quote who="love9sick" reply="11" id="2086778"]Honestly the only way time exists is when events are spread out. The interval between these events are the units of time. Light is weightless which is why it can travel exactly at the instant of time. All events happen instantly relative to the speed of light.
Time exists everywhere, all the time, whether events are spread out in time or not. It's actually much, much more complex than that - because the concept of simultaneity somewhat false apart. If you stand at a train station and drop two identical balls from identical heights, you will observe those two balls hit the ground simultaneously. But if I am in a train, speeding through the station at 0.9 times the speed of light, I will see the balls hit the ground at different times. Simultaneity is dependent on the observer. However, I could sit on my train and, knowing my speed compared to the station, decide to calculate when you saw the balls hit the ground. So, the point I'm getting at is, saying that "the only way time exists is when events are spread out", I guess you're right - except there is always some reference frame (really, an infinite number of them), in which the events do not occur simultaneously.
You are right, although I think accidentally! The definition I quoted above is actually incomplete. It is based on the resonance frequency of caesium on the Earth's geoid. This means that, if you are on a spaceship moving away from Earth very quickly, and you measure the resonance frequency of Caesium 133 to determine a second, you would have to make appropriate relativistic corrections (for both the velocity and gravitational dilation) in order to determine the actual SI second. So yes, the second is a value we choose for the speed we are moving through time, but it is 100% convertible to any other reference frame. My point here is that we did not invent time in any way, shape, or form. Just like deciding on a standard spatial distance like the meter does not mean we invented space, deciding on a standard temporal interval does not mean we invented time.
That's the problem with a lot of modern physics. It's extraordinarily difficult to understand, even conceptually. If you understand the mathematics behind it, it makes things it a lot easier to understand; but even for people with a background in math it can take quite a while - and lots of effort - to get through it all. For the average person, whose mathematical education largely ends after high school, that's pretty much out of the picture. Sadly, I think that's one reason why fewer and fewer people are getting into the mathematical sciences.
With the discussion of Time in the last couple of posts, you may find the following an interesting read:
But if time doesn't exist, why do we experience it so relentlessly? Is it all an illusion?
Yes, says Rovelli, but there is a physical explanation for it. For more than a decade, he has been working with mathematician Alain Connes at the College de France in Paris to understand how a time-free reality could give rise to the appearance of time. Their idea, called the thermal time hypothesis, suggests that time emerges as a statistical effect, in the same way that temperature emerges from averaging the behaviour of large groups of molecules (Classical and Quantum Gravity, vol 11, p 2899).
Imagine gas in a box. In principle we could keep track of the position and momentum of each molecule at every instant and have total knowledge of the microscopic state of our surroundings. In this scenario, no such thing as temperature exists; instead we have an ever-changing arrangement of molecules. Keeping track of all that information is not feasible in practice, but we can average the microscopic behaviour to derive a macroscopic description. We condense all the information about the momenta of the molecules into a single measure, an average that we call temperature.
According to Connes and Rovelli, the same applies to the universe at large. There are many more constituents to keep track of: not only do we have particles of matter to deal with, we also have space itself and therefore gravity. When we average over this vast microscopic arrangement, the macroscopic feature that emerges is not temperature, but time. "It is not reality that has a time flow, it is our very approximate knowledge of reality that has a time flow," says Rovelli. "Time is the effect of our ignorance."
Bah! Screwed up the quoting (and no edit button), but you get the idea.
Wow, thank you for the read! I've never heard of this theory before, it's definitely different.. and bizarre! But also very neat and rather elegant. I looked up the actual paper and it's an even better read than the article about it. Although it seems that the article about it is somewhat sensational - the paper doesn't go as far as to state or show that time is an illusion (the word illusion, or any similar word, is never used).
A good quote putting this in perspective is this: "it is wrong to say that time is an illusion. It is just reducible or non-fundamental, in the same way that consciousness emerges from brain activity but is not illusory."
Welcome Guest! Please take the time to register with us.
Sins Forums
GalCiv2 Forums
Elemental Forums