Planck Definition and 381 Threads

http://spaceinvideos.esa.int/esalive You can watch a live webcast of the Planck results, 10 am CET 21st MArch . Lets hope they discover something exciting and its not just WMAP to a few more decimal places. But of course there's strill the polrisation data 1 year away , nice article here...

surely if you keep adding smaller and smaller sides to the snowflake they will become even smaller than the Planck length and so how can the perimeter be infinite- or is the infinite perimeter only theorteically possible with maths, but not actaully acheivable?

In case you didn't know already the first all sky Cmb map will be released at a press conference at ESA HQ March 21st http://smsc.cnes.fr/PLANCK/Fr/GP_actualites.htm This will be followed by a conference to discuss the cosmological data in Holland April 2nd-April 5th...

What would happen if the entire universe would be reduced in size by several orders of magnitude. I mean not just the distances between the galaxies but also the size of every planet, every atom, every nucleus and so on. That also means the strength of all forces would have to become smaller...

This comes form the wiki article on quarks: Does that mean that when two Quarks come as close to each other as the Planck distance 10-33m then gravity must be taken account if one is to understand their movement? I know vaguely that the Planck energy is the point at which a black hole...

I am trying to remember a quote I once read by Max Planck. Max Planck, Albert Einstein, and other scientists were at a meeting or convention regarding relativity or some other scientific theory. Planck said something like "As the [some scientific theory] cannot extend the time for this...

Hello, Planck units are defined here http://en.wikipedia.org/wiki/Planck_units Length, mass and time are defined via G, c and \hbar and do not involve kB; But temperature contains all G, c and \hbar and kB; Perhaps this is okay; just seems "uneven" that kB appears with a zero power in...

Can the Planck relation, and the Heisenberg and the time-energy uncertainty principles be derived, or produced, from the equations of General Relativity?

I am just an interested high school physics student so I don't really know much about the subject, but I am given to understand that a Planck length is the smallest length. It cannot be further subdivided and no length smaller can be measured even with a great advancement in measuring...

I just noticed this has been announced by ESA, maybe its old news, so apologies if it is; but it looks like we have a date for the first cosmological data release of PLanck http://congrexprojects.com/13a11 2-5 April 2013 "The objective of the conference is to present and discuss the...

Hi all, Does anybody can provide a source that can prove Planck's length from scratch ? I mean from classical mechanics to quantum mechanics, a pedological proof/derivation ? Thanks in advance.

This paper - http://arxiv.org/abs/1211.3816 - by Beckenstein is fascinating. I would like to know if the experimental test proposal is realistic.

Hello all . We know Planck length is and universe was in that density at big bang . Is that mean there was dimension at that time ? I mean , can we move in Planck length ? like up , down, right, left, forward, backward ؟

Today I was driving down the road, on the side of the road, there was a fence made of many vertical slats. I noticed that that sun was blinking on and off like a strobe light, as each individual slat would shield the sun, and each space in between the slats would expose it. I thought, if my...

Assuming that a Planck length is the smallest unit of distance, I propose this: Assume there was a circle of radius r and had an area of A. If I would increase this circle's area by 1 Planck length^2, would the radius change? The radius would theoretically change by less than a Planck...

Hi there, I am reading something on quantization, semi-classical approximation of a quantum system and related topics. There are few statements are pretty confusing. First of all, in many material, whenever they mention the quantization, they refer to a commutator, like [\hat{A}, \hat{B}] =...

Let me start off by saying that I really only have a few weeks experience beyond the introductory physics courses, so I apologize in advance for any gross misconceptions I have. In trying to understand Planck's theory, I came upon a number of confusions that I am having trouble reconciling...

This can be read in the ESA site on news about the Planck probe: " Planck has also detected a mysterious haze of microwaves that presently defies explanation. It comes from the region surrounding the galactic centre and looks like a form of energy called synchrotron emission. This is...

Can someone explain to me this paper in laymans terms? I don't get it. They are claiming discovery of a new method of acceleration of cosmic rays in the centre of the galaxy. URL: http://arxiv.org/abs/1208.5483 Paper: Planck Intermediate Results. IX. Detection of the Galactic haze with...

Has the Planck satellite observed any gravitational waves yet? I'm pretty sure that gravitational waves were formed when gravity split from the other forces at 10^-43 seconds but I could be wrong. Anyhow, if we do detect them, will we be looking at the first Planck time in our universe's...

Wouldn't the shortest interval of time and the smallest object always be an infinite #? How can you ever stop splitting something in half? Hard to fathom on that level I guess. Logic tells me they are infinite?

If space contracts relative to the motion of an observer, would two observers traveling at different speeds disagree on the Planck length? Or is the Planck length constant such that two observers would agree on the Planck length, but would disagree about how many Planck lengths long certain...

Homework Statement This isn't actually homework but I'm really interested in finding the solution. So I have the langevin equation dy/dt = -dV/dy +η(t) where V(y) = -by^3/3 + ζy how can I turn this into a fokker-planck equation? Homework...

I was listening to people in another forum discuss the idea of Quantum Immortality, and the thought occurred to me, is there a point where the odds of something occurring become so small, that they aren't just extremely, extremely remote, they are in fact, zero? For example, if we took a...

This comes from Alex Vilenskin's Many Worlds in One: I didn't think there was such a distance below the Planck length.

Many of us, probably most, know Smoot and Mather got the 2006 Nobel "for their discovery of the blackbody form and anisotropy of the cosmic microwave background radiation." But there is more to the story, other scientists other instruments other features of the early universe discovered in the...

If we imagine 2+1 dimensional gravity, I think that this influences on Planck distance and time. Because attraction between two bodies can be described: F = m_1 m_2 G/r F= force, m are masses, G is changed gravitational constant and r is distance between two bodies. So G does not have...

Planck length and Planck time are constants, correct? If spacetime changes for an observer who accelerates to subluminal velocities, what happens to these units? If they're constant I'm guessing they can't be "stretched" or "squashed". So do they change in number for a given measurement (say...

Do Planck units apply inside of black holes? Are they modified? Or are they irrelevant? If some Planck units remain unchanged and applicable in black holes, which ones would those be?

Hello everyone. After reading most of the existing topics on the Planck length, I still haven't found what the Planck length really is. Some references say nothing can possibly be smaller than the Planck length, whereas others say it's just a threshold below which "special" things happen...

If there is an irrational solution to an equation for where a particle should be, for example from an ODE, then what effect does Planck length have on that? Does the actual position of the particle get rounded to an a multiple of the Planck length? If it does, wouldn't that imply there is a loss...

Planck constant "V" in E=qV question 1. Homework Statement I am trying to prove Planck's constant using LEDs. So far I have measured several LED's wavelengths using a spectrometer and from this their frequency. This will be f in the equation h = E/f. For E I put the LEDs in a forward biased...

do you know where fokker-planck equation comes from?

Here is a study in distances based on powers of ten of the meter. It gives easy-to-see graphic examples of relative size, from the Plank length out to the Observable Universe. Imho, a great teaching aid. http://www.newgrounds.com/portal/view/589217

Quantum Gravity only becomes a problem when we probe below the Planck scale. This is because we don't know what occurs inside a singularity in a Black Hole or in the initial condition of the Big Bang when the universe was supposed to be in Planck density. The Planck scale is also the origin of...

What are the reasons for scientists believing the Planck scale is the smallest unit of length? I have been hearing a lot of this length scale recently and i know we can't even do expiremental research at these small of levels. I'm wondering where they got the idea that strings [from string...

If I'm not mistaken, it is thought that space is divided up into quantized little indivisible chunks, the size of which is called the Planck length. Also, the space of the universe is thought to be expanding. We could have 2 objects stationary relative to one another at some time t_0, then...

I've been looking at the various Planck units, and I'm wondering how they are constructed from the constants involved. Like is there any physical reasoning behind those equations? I've looked all over the place for derivations of the equations or what the actual physical meaning of the units...

Time and time again I always hear people say that Planck Lengths are the smallest units of meaningful distance. But I don't think this implies nothing can be smaller than this or that spacetime is discrete, correct? It just means talking about anything smaller than this would be like talking...

First time poster so please be gentle... E = h * f f = c / wavelength 1) Is there a theoretical limit on maximum f (minimum wavelength of Planck length)? 2) Is there a theoretical limit on minimum f of 1 (maximum wavelength of c)? (ie// the maximum distance that a photon can cover in...

Is the universe similar to Conways game of life? Let me elaborate. For us, a second is the unit of time and its a pretty short unit of time. But then at the atomic scale, a second is a pretty big unit of time. Everything we do is in the order of seconds or maybe milliseconds. But so much happens...

Homework Statement Hi Guys, Just started a Mechanical Engineering Course and in my Physics this came up, I'm really confused and don't know were to start. I was wondering if anyone could shed any light on the subject. Thanks guys. Three of the fundamental constants of physics are the...

I was watching indepth on cspan booktv with Michio Kaku and he says that the Planck time has not be proven. I thought it was a proven fact, but he says it is still theoretical and we have no evidence for it yet. Is this true?

It is widely recognized in physics textbooks that Planck constant is a "universal constant". But I nerver see a proof. As we know, in the special theory of relativity, c is a universal constant, namely a Lorentz invariant, which is Einstein's hypothesis. But How do we know the Plack constant h...

Please help me find "Entropy and Temperature of Radiant Heat" by Max Planck I would like to read "Entropy and Temperature of Radiant Heat" by Max Planck in English. Please help me find this if you have any ideas how. Thank you!

It is perfectly possible to derive, for instance, the Maxwell distribution of speeds in a heuristic way with only two things: 1. The Gibbs hypothesis, which says that to count the number of states at speed v you take all the points in phase space between v and v+dv in velocity space. This...

I want to know as much as I can about this picture. http://www.esa.int/images/PLANCK_FSM_03_Black.jpg Its the most beautiful picture I've ever seen. What an accomplishment. Must have been one heck of a party when they seen this for the first time. Now here's what my brain sees when I...

For my own edification. The Planck Function when integrated over all wavelengths will give the radiated power per unit area for a black body. Would I be right in thinking, that if I had a known temperature for the black body source or indeed a kT value for that source that by using the...

Quick question: Is Planck time the same in all reference frames? Is it different at, say, half the speed of light than at a relatively stationary point? What about in a severe gravitational field, like a black hole?

Locally, photons "blue-shift" when falling down a gravitational field. What happens when they arrive at the Planck frequency? Do they turn back into matter?