Linked Questions

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0answers
198 views

Planck length, planck time, and planck rotation? [duplicate]

given that there is a fastest speed at which anything can travel in our universe,299,792,458 meters per second, that seems to imply there may be a smallest distance in our universe, so first of all, ...
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0answers
44 views

How Einstein thought experiment clock works in quantum world? [duplicate]

According to Einstein's thought experiment, imagine a clock but this time the distance between mirrors is one Planck length $\ell_p$. If we move the spaceship (with clock on board) at velocity $v$. ...
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0answers
15 views

Quantization of length [duplicate]

Plank length is considered to be smallest length possible in the universe. But since it is derived only from some known constants and it's value is derived from dimensional analysis, it doesn't ...
130
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2answers
21k views

Does the Planck scale imply that spacetime is discrete?

On a quantum scale the smallest unit is the Planck scale, which is a discrete measure. There several question that come to mind: Does that mean that particles can only live in a discrete grid-like ...
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5answers
15k views

How to get Planck length

I know that what Planck length equals to. The first question is, how do you get the formula $$\ell_P~=~\sqrt\frac{\hbar G}{c^3}$$ that describes the Planck length? The second question is, will any ...
24
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3answers
6k views

If energy is quantized, does that mean that there is a largest-possible wavelength?

Given Planck's energy-frequency relation $E=hf$, since energy is quantized, presumably there exists some quantum of energy that is the smallest possible. Is there truly such a universally-minimum ...
24
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4answers
9k views

Is there a maximum possible acceleration?

I'm thinking equivalence principle, possibilities of unbounded space-time curvature, quantum gravity.
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4answers
6k views

Can a photon have a wavelength less than the planck length?

Well? Maths if necessary, please. Would the photon effectively have no wavelength?
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4answers
2k views

Are laws of nature absolute or are they just very good approximations? [closed]

Newton's second law, for example, states that $F=ma$. Is this absolutely true, down to the smallest possible unit of measurement? Or is it just a handy approximation that happens to work extremely ...
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2answers
1k views

Is the Planck length the limit below which our physics does not make sense? And if so, why is that true?

I've been reading Physics SE answers on Planck units such as this one and this one. The general picture I get is that much of what is said about the Planck length (and the associated Planck units) is ...
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4answers
1k views

How far apart do two objects have to be for there to be negligible force between them?

Inspired from the commentary on this question. How far apart do two objects have to be for the gravitational force between them to be negligible? By negligible I mean, that it could never be ...
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1answer
2k views

What things are smaller than the Planck length?

I recently read Is the Planck length the smallest length that exists in the universe or is it the smallest length that can be observed? The general agreement is that the idea that the Planck length ...
0
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1answer
501 views

Is the minimum mass of a black hole the planck mass?

Leonard Susskind said "It's thought to be the mass of the smallest black hole that can form" (or something like that when referring to the planck mass in his string theory lectures) and I've always ...
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2answers
413 views

Does calculus work on the quantum scale [duplicate]

I have read somewhere that Leibniz championed the idea that the world is continuous as this was needed for his (or maybe Newtons) new invention (or discovery?) of calculus. But if I am not mistaken a ...
1
vote
1answer
252 views

Is there a proposed minimum amount of energy?

I've read that "The Planck length is believed to be the shortest meaningful length (...)"(1). Regardless of the factual accuracy of this claim, I'm wondering if: is there a related concept regarding ...

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