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-5
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1answer
130 views

Describing physical constants in alternate wording; c = there can only be 671million miles of space for every second of time [closed]

This spawns from part of an answer to a question I asked. All sorts of things go to 0 and/or ∞ if you start boosting at c, and so you cannot boost into and out of a photon's frame. It ...
0
votes
1answer
119 views

Zero uncertainty constant and a unit change

So, we know the speed of light with zero uncertainty. We also know that values of $\epsilon_0$ (electric constant) and $\mu_0$ (magnetic constant) are known with zero uncertainty. My questions are ...
0
votes
0answers
99 views

Why there can't be infinitely small existing?

Why there can't be infinitely small existing? I am not suggesting it can or cannot. I am asking can there be an absolute or reasonable answer to that question.
3
votes
2answers
554 views

What is the smallest existing thing in theory and law?

What is the smallest existing thing in theory and law?
7
votes
2answers
334 views

What constant varies in the fine structure constant?

Using the renormalization group approach, coupling constants are "running". If we apply this to the fine structure (coupling) constant, we do know that, e.g., at energies around the Z mass, $$\alpha ...
1
vote
1answer
66 views

measure higher frequencies then half of Planck-frequency?

The maximum frequency is defined by the Planck frequency $\omega_P$. Also there is the Shannon theorem which tells us that to lossless capture a signal, you have to sample it with minimum of the ...
8
votes
0answers
144 views

Why is the Planck length the shortest measurable length? [duplicate]

I quote from the Wikipedia article on Planck length: According to the generalized uncertainty principle, the Planck length is in principle, within a factor of order unity, the shortest ...
3
votes
1answer
141 views

Units for physical constants

Someone told me that units for $G$ and $\epsilon_0$ (gravitational constant and Coulomb's constant) are placed there simply to make equations work dimensionally and that there is no real physical ...
3
votes
3answers
180 views

Curious relation between the dependance in ℏ of Planck units and units dimensions

Looking at Planck units, there seems to be a curious rule between the dependance in $\hbar$ of a Planck unit and the unit dimensions of the corresponding physical quantity. Let the dimensions of the ...
1
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0answers
105 views

Has unnaturalness motivated new ideas in physics?

The cosmological constant problem arises because the natural scale of the cosmological constant is $10^{120}$ times larger than what we observe. This implies that the dimensionless constant is much ...
12
votes
6answers
2k views

Why does the speed of light $c$ have the value it does?

Why does light have the speed it does? why is it not considerably faster or slower than it is? I can't imagine science, being what it is, not pursuing a rational scientific explanation for the speed ...
2
votes
2answers
306 views

Newton's Law of Graviation: Why $G$ and not e.g. $\dfrac{1}{4\pi G_0}$?

I've been wondering, in Coulomb's Law, $k_e = \dfrac{1}{4\pi\epsilon_0}$. Therefore, why do we use $G$ in Newton's Law of Gravitation? What if the constant is more like Coulomb's Law, e.g. $G = ...
-1
votes
1answer
122 views

Hubble Constant and Planck Constant

Has there been any effort to understand Hubble's limit as a quantum phenomenon? It seems like they are suggesting the same thing.
-6
votes
1answer
280 views

Where the fine structure constant $\alpha$ is speed parameter of electron $\beta_e$, How can it be a constant?

The fine structure constant $\alpha$ actually is speed parameter of electron $\beta_e$, moving around proton in hydrogen atom. $v_n=\frac {\alpha_c}{n}=c\frac {\alpha}{n}=c\frac {\beta_e}{n}$ How ...
-5
votes
1answer
143 views

How do I publish a physical constant [closed]

I think what i've found is a physical constant that is a physical quantity, universal in nature and constant in time. but It contrasted with a mathematical constant, which is a fixed mathematical ...
16
votes
5answers
2k views

How can the speed of light be a dimensionless constant?

This is a quote from the book A first course in general relativity by Schutz: What we shall now do is adopt a new unit for time, the meter. One meter of time is the time it takes light to travel ...
0
votes
0answers
169 views

How many physical constants should there be?

I see there are different accounts on the number of physical constants. Is there any theory predicting what the number of physical constants is? I agree there should be at least one but I have no ...
6
votes
3answers
282 views

Is there a simple way to compute some physical constant from Feynman diagram statistics?

I've been playing around writing some software to generate Feynman diagrams for QED, respecting the vertex "rules" described here, and avoiding creating isomorphic duplicates. So from a starter ...
2
votes
1answer
653 views

What really is Planck's constant and what are its origins?

In the physics texts I have read and other info online, they says Planck's constant is the quantum of action or that it is a constant of the ratio of the energy of a particle to its frequency. Im ...
10
votes
3answers
3k views

Have I discovered how to calculate the proton's mass using only integers?

Could it be possible that the mass of the proton can be calculated by a series of integer sequences? Or is this just a curiosity? $$\sum_{m=1}^{\infty } \frac{1}{10^{26}(m^2+1)_{2m}}=$$ ...
3
votes
5answers
308 views

Is the gravitational constant $G$ a fundamental universal constant?

Is the gravitational constant $G$ a fundamental universal constant like Planck constant $h$ and the speed of light $c$?
5
votes
1answer
253 views

Definition of Fine-Tuning

I've looked in and out the forum, and found no precise definition of the meaning of fine-tuning in physics. QUESTION Is it possible to give a precise definition of fine-tuning? Of course, I guess ...
4
votes
5answers
1k views

Planck mass is about the mass of one eyebrow hair

Unlike most Planck units named after "Planck" such as Planck length, Planck temperature, etc, the Planck mass seems more closed to daily life. It is about $10^{-5}$g, same order of magnitude of one ...
0
votes
1answer
142 views

How is charge measured and mass of the electron at the same time?

There are few constants that usually come together, $e/m$ also $h/e$. How are they decoupled? If the speed of light is "derived" as Wikipedia states how meter defined and time?
2
votes
3answers
484 views

Planck time, distance, mass? Why do we take those values?

Say we want to make an educated guess for critical values of time, distance and mass, where quantum gravity effects are supposed to be non-negligible. These values are given the prefix "Planck-". Now, ...
1
vote
3answers
529 views

The vacuum light speed: Is it really constant, i.e., independent of location in space-time?

I am by no means an expert in this field, however something puzzles me about the speed of light and the relativity of time and space (space-time). Is is universally acknowledged that the speed of ...
7
votes
3answers
324 views

why there is no accuracy of the measured value of $G$?

With the advancement of Modern Technology still there is no accuracy of the measured value of $G$ Gravitational Constant, why!?
4
votes
1answer
135 views

Official definition of astronomical units

As it is relatively easy to find an official value for a large number of physical constants, (thanks to CODATA), it is not so easy for some units widely used in astronomy (Wikipedia, Google and IAU ...
8
votes
2answers
2k views

Has the speed of light changed over time?

Could someone judge my (stoner) hypothesis that the speed of light has changed over time -- ie. as the universe has expanded in volume light has slowed down, perhaps going so far as back to the big ...
3
votes
2answers
248 views

Was Planck's constant $h$ the same when the Big Bang happened as it is today?

Was Planck's constant $h$ the same when the Big Bang happened as it is today? Planck's constant : $$h= 6.626068 × 10^{-34}\, m^2 kg / s,$$ $$E=n.h.\nu,$$ $$\epsilon=h.\nu$$
5
votes
1answer
330 views

Variable speed of light in cosmology

In this paper, D. H. Coule argues that warp drive metrics, like the one proposed by Alcubierre, require the exotic matter to be laid beforehand on the travel path by conventional travel. At section 5 ...
4
votes
3answers
177 views

In what subfields and how far can the naive limit $c\rightarrow\infty$ of special relativity be carried?

Even if many interesting similarities between the classical and the quantum mechanical framework have been worked out, e.g. in the subject of deformation quantization, in general, there are some ...
0
votes
2answers
87 views

Why is the thomson cross section constant over cosmological time?

In all astrophysical calculations I'm aware of, the thomson cross-section (for electron scattering) is taken as a constant in time, why is this the case? I have only weak experience in cosmology and ...
11
votes
5answers
2k 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 ...
3
votes
1answer
201 views

Were the physical constants chosen randomly by the nature?

Were the physical constants chosen randomly by the nature or it was determined by some source of… matter(?). I really don't have idea. If you could help me it'd be awesome.
13
votes
4answers
1k views

Is the Avogadro's constant equal to one?

Question: Is the Avogadro's constant equal to one? I was tasked with creating a presentation on Avogadro's work, and this is the first time I actually got introduced to the ...
6
votes
1answer
358 views

Is there an explanation for the 3:2:1 ratio between the electron, up and down quark electric charges?

I understand that the NNG formula relates $Q$, $I_3$, and $Y$ and can be derived in QCD; does this unambiguously predict the electric charge ratios without making assumptions about the definitions of ...
4
votes
1answer
160 views

Fine Tuned Universe

Is the fine tuning that cosmologists talk about (that our Universe is fine tuned for intelligent life) is the same as the fine tuning of the squared mass parameter of the Higgs in the Standard Model? ...
2
votes
3answers
523 views

What are the physycal meaning of universal constants such as the magnetic, electric and gravitational constants?

I know that: $G=6.67300 × 10^{-11}\dfrac{Nm^2}{kg^2}$(Gravitational constant) $K_e=9×10^9\dfrac{Nm^2}{C^2}$(Electric constant or Coloumb's constant) $k_m=1×10^{-7}\dfrac{Ns^2}{C^2}$(Magnetic constant) ...
1
vote
3answers
441 views

What is the reason behind specific values for charge of electrons, protons?

Why do things like protons and neutrons have specific values. Also speed of light is a speed in which even if you go towards it, the speed does not vary. But why does light have to travel at speed?
10
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7answers
2k views

What is the proof that the universal constants ($G$, $\hbar$, $\ldots$) are really constant in time and space?

Cavendish measured the gravitation constant $G$, but actually he measured that constant on the Earth. What’s the proof that the value of the gravitation constant if measured on Neptune would remain ...
-1
votes
1answer
112 views

How can constants… change?

I recently noticed that the value of Planck's constant has changed on Wikipedia. The value that I had in mind (from Google), $6.626068\cdot{}10^{-34}\text{J.s}$, has changed to ...
4
votes
4answers
1k views

Can Planck's constant be derived from Maxwell's equations?

Can mathematics (including statistics, dynamical systems,...) combined with classical electromagnetism (using only the constants appearing in chargefree Maxwell equations) be used to derive the Planck ...
4
votes
5answers
755 views

Why are $\mu_0$ and $\epsilon_0$, which appear in electrostatics and magnetostatics, related to the speed of light which appears in electrodynamics?

$\epsilon_0$ and $\mu_0$ appear in electrostatics and magnetostatics. When we include time varying fields we have electrodynamics and the appearance of c which turns out to be related to $\epsilon_0$ ...
3
votes
1answer
120 views

The fine structure non-constant

If the fine structure constant is different in different parts of the universe, then what would happen if we travelled to those regions? (I realise this is completely impossible as they are ...
1
vote
2answers
218 views

The time component is $\gamma m c$, so shouldn't $E=mc$?

Basically, the book is Brian Cox's Why Does $E=mc^2$?: (And Why Should We Care?). I just finished Chapter 5, where we derived the spacetime momentum vector (energy-momentum four vector, as he ...
1
vote
1answer
816 views

What do physicists mean when they say “speed of light”?

Does it make sense to say, "The speed of light varies?" Some may say right off the bat "Yes, it changes as a wave passes through a different medium." However, I'd like to say no, because when I hear ...
2
votes
3answers
186 views

What widely recognized organizations set standards used by physics?

I recently answered a question about the meaning of the word "dimension" as used in physics. In that response, I provided the definition given in the International Vocabulary of Metrology (VIM) and ...
6
votes
1answer
639 views

Why can you remove the gravitational constant from a computer game simulation?

I've seen in a few gravity simulation games (ie. bouncing balls) the equation: force = G * m1 * m2 / distance^2 shortened to this by removing the gravitational ...
5
votes
2answers
600 views

How can I explain the scientific basis of the constant speed of light to a $c$-decay proponent?

This Phys.SE question asks why and how the speed of light is constant. I would like to ask a related, almost converse question: Given that the speed of light is constant, how could I explain to a ...