Talk:Planck time
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[edit] Concerns regarding following statement
Does anyone else have an issue with the following under 'Simple Definition':
"The speed of any object is limited by Einstein's laws of relativity, which state that nothing can travel faster than the speed of light in a vacuum (denoted c)."
I understand that this is for a simplified explanation, but it's just plain not true. Einstein only stated that an objects mass would become infinite if traveling at the speed of light. Also, faster-than-light observations and thoughts have been carried out and discussed here:
http://en.wikipedia.org/wiki/Speed_of_light#.22Faster-than-light.22_observations_and_experiments
I didn't want to alter the original article since I'm new to the wikipedia, but wanted to leave note of this in case the author would like to respond and possibly reconsider an edit.
Respectfully,
Dave Quirus 26 Aug 2005
[edit] 14th January 2005 Changes
Thanks Jim Wae the LaTeX rather mucked up that's not my best attribute, what did you think of the changes the article needed to be merged with Planck's Time so I more-or-less added it as a simple explanation for Planck Time.
I hope I pulled it off, I think that article still could be improved on though. Jordan14 21:09 16th Jan 2005
[edit] Merger from Planck's time and beyond
I've redirected Planck's time to this page. I didn't find any material on that page that adds to any on this one and it's far less (i.e. not) wikified. I've reproduced the text here for anyone who disagrees and wishes to reapply any of it:
- Planck's Time
- Planck's Time is how long it takes for light to travel Planck's length.
- At Planck's length relitivity breaks down and actions across smaller lengths are worthless, as an effect this is the smallest length of significance.
- As described by relitivity nothing can travel faster that the speed of light.
- So to find Planck's Time/Time Quanta - the smallest amount of time. We have to do the sum:
- Planck's constant (The smallest distance) divided by The speed of light (The fastest speed) and this will equal the smallest part of time, which is Planck's Time/Time Quanta.
- As and effect we get the following value for Planck's Time:
- 1 x 10^-34m divided by 3 x 10^8 m/sec
- So this means Planck's Time is about 3.3 x 10^-44secs. This is the smallest amount of time.
That done, I think that this article is confusing, for several reasons.
First, there is no mention of the fact that that time is discrete is a very recent finding, it is not universally accepted, and its ramifications are far from fully understood.
Second, the value is derived twice, two (apparently) different ways. The second, the simpler, is just simply the mathematical expression of the definition of of the number. The first is essentially the same thing, but doesn't make clear except to a well informed reader how you get from d = st to tp = (hG/C^5)^1/2 (i.e. that (hG/C^5)^1/2 = ((hG/C^3)^1/2)/c = lp/c.)
Third, the structure seems backward, in that it presents the "simple definition" in the middle of the article, rather than proceeding from simple to complex. Planck length, while not perfect or comprehensive, would seem to provide a good template.
Also, while the fact that things get really wacky before Planck time = 1 is likely notable enough to include in the article, the way its presented now makes it seem like that that is a defining factor for the Planck time.
And, I think the use of the of the word "nonsense" in the second section is problematically vague. I've seen the phrase "does not have meaning" used and think that that (or similar) would be more epistemologically rigorous.
After all that, I'm not going to edit it. I'm not expert enough to do more than reorder the article and apply (what I think should be) a template for the article and leave it only half-filled. Plus, I have no competence with the math markup. But I hope these ideas help someone to edit, improve, expand this article.
VermillionBird 20:04, 2005 Mar 7 (UTC)
[edit] A discrete world?
So there's the Planck length and the Planck time: does this mean the world can be thought of as a 3 dimensional grid, each cell sized to the Planck length, and iterations running in every Planck time (i.e. the Planck time is the "FPS value" of the universe)?
> The Planck time is the time it would take a photon travelling at the speed of light to cross a distance equal to the Planck length. However, this may not be taken as a "quantum of time."
Please elaborate. If it can't be taken as a quantum of time, there must be a reason. 67.67.250.168 02:41, 19 March 2006 (UTC) Keith
The planck time is the tiny gap,'between the tick and the tock', referred to as the present, that separates the future from the past. Within the Planck time particles such as positrons, electrons, and photons can travel in both directions of time. In the case of the electron it enables the recapture of virtual photons that would otherwise lead to the rapid loss of their charge/magnetic moment over time. Richard Feynman's description of the e->e- + p+>photon + e- pair-producing contribution to the fine structure of atomic spectra was explained by him as a process involving the emission of a photon by the electron accelerating relativistically in the vicinity of the nucleus. The photon is transformed into an electron positron pair. The positron, in the Planck time, travels backwards in time to annhilate with the original electron, resulting in a single electron and photon/s resulting from the annhilation both leaving the Planck time and travelling forwards in time. Planck space and Planck time are intimately associated with the Uncertainty Principle and help to explain the paradoxes raised by quantum mechanics such as non-locality and complementarity. Colin Cumming 23 March 2006.
[edit] Referenced from Time under "Time quanta"
Time references this topic in the "Time quanta section": Time#Time_quanta. I think that is misleading and I opened a discussion at Talk:Time#Time_quanta.3F Your opinion? 206.169.169.1 18:43, 4 October 2006 (UTC)
