# Tagged Questions

794 views

### Is there any relation between Planck constant and Gravitational constant?

Why is the Gravitational constant about $10^{23}$ times of the Planck constant in SI-units? Is there any relation between them? I mean Planck constant is about $6.6\times 10^{-34}$ $Js$ and ...
244 views

### What prediction led to the vacuum catastrophe?

The disagreement between predicted and measured energy density of the vacuum is one of the great unsolved problems of science. According to this book the predicted energy density was obtained as ...
208 views

### Fundamental Constants in a theory of everything (TOE)

Do physicists ever expect to be able to derive the fundamental constants of nature from theory? For example, if string theory or some other theory unites the four forces, would the theory be ...
140 views

### Why Planck scale is so important?

I know that Planck scale is the scale where both, gravity and quantum effects are relevant simultaneously. Are there more reasons?
89 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.
507 views

### What is the smallest existing thing in theory and law?

What is the smallest existing thing in theory and law?
64 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 ...
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 ...
475 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, ...
### 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 : $$h= 6.626068 × 10^{-34}\, m^2 kg / s,$$ $$E=n.h.\nu,$$ $$\epsilon=h.\nu$$
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 ...