# celtschk

A quiet enigma. We don't know anything about celtschk yet.

## Posts

See all 13 »In special relativity, spacetime coordinates are normally given as $$(ct, x, y, z) \tag{S}$$ with the metric being either $$g = \operatorname{diag}(-1,1,1,1) \tag{+}$$ or $$g = \operatorname{d...

1 answer · posted 4y ago by celtschk · last activity 4y ago by dmckee

Inflation in cosmology refers to a phase of the early universe where the universe expanded extremely fast. And the universe expanding quite literally means the space getting bigger. As you noticed...

posted 3y ago by celtschk

To understand this, it helps to look at a dimension less. Imagine, you're having a dispute with a flat-earther about whether the earth is a sphere or a flat plane. Moreover, there's a third person...

posted 3y ago by celtschk

Change in momentum is force times time. On the other hand, change in kinetic energy is force times distance (more accurately, the component of the force along the movement times distance; a force p...

posted 3y ago by celtschk

Your mistake is that you did a second derivative of $L$, taking the derivative according to both degrees of freedom together. Instead you need to make a separate equation for each degree of freedom...

posted 3y ago by celtschk

To start with, black holes in the GR model don't radiate. At all. Even Hawking radiation isn't predicted by GR. Rather, it is predicted by doing quantum mechanics in curved spacetime. That is, you ...

posted 12d ago by celtschk

As you probably know, one of the postulates Einstein's Special Relativity is based on is that all observers see light in vacuum go at the same speed $c$. Now consider a lamp at rest relative to Jo...

posted 3y ago by celtschk

Yes, that would the obvious interpretation of that equation in one dimension. Note also that in that case, the divergence also reduces to the ordinary derivative. In other words, in one dimension,...

posted 2y ago by celtschk

Reputation | 366 | |

Number of top-level posts | 1 | |

Number of answers | 12 | |

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Number of edits made | 7 |

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