As the particle nears the horizon, its positive momentum transforms into positive energy while its negative energy turns into negative momentum. Though this brief transition period of negative energy could pose a challenge, it is fortunately short-lived (with some hand-waving). Solution 1: As per my understanding, any observer, regardless of being inertial or not, having […]

# Category: General relativity

## Acceleration Counters Gravitational Time Dilation

The inquiry is regarding the comparison of time shown by two different clocks. One of the clocks, clock A, is situated at the summit of a mountain whereas the other one, clock B, is present in a stationary helicopter flying at the same height as clock A. Both the clocks are positioned at the same […]

## Decoding the Mystery of Gyroscopes

Although it is feasible to establish a configuration where the transfer of angular momentum occurs between the gyroscope and the Earth, it is not necessary to consider this scenario when accounting for the initiation of gyroscopic precession. For further information, you can visit https://www.ericcogyro.com/application/. Can you explain how a MEMS gyroscope can provide orientation? Question: […]

## Is Our Planet Approaching the Sun?

Although not all cosmic rays move at relativistic speeds, the Earth is capable of reaching such speeds. Ultimately, the Earth’s orbital speeds can approach those of light. Solution 1: The Earth’s position in orbit around the sun is maintained by the spacetime distortion that is produced due to the mass of the Sun. This phenomenon […]

## Questioning the Large Diameter of the Universe Despite the Limitation of Light Speed [duplicate]

When asked about the expansion of space, a brief explanation is that the particles are pushed further apart without exceeding the speed of light. Once the stretching has occurred, it’s important to note that light continues to move at its normal speed, unaffected by the expansion. To demonstrate this, one can ask if the distance […]

## Examining the Stress-Energy Component of Einstein’s Equation through the Schwarzschild Solution

The fact that $R_{munu} = 0$, which is the Einstein field equation for a vacuum solution, does not render the Einstein field equations obsolete. This equation imposes certain conditions on the ansatz used for the Schwarzschild metric and is crucial for its derivation. Additionally, it should be noted that the stress tensor $T^{munu}$ in the […]

## Is the speed of light slower than gravity?

No, it does not . Gravity waves can’t travel faster than the speed of light in the “direct” path, they will always appear to us as if that is the speed they are traveling. However, if space was stretched away from the source, it would take longer for them to get there, but they still […]

## Existence of Singularities in Black Holes: Is it Universal?

Black holes do not have singularities Black holes do not have singularities . Since all matter of a black hole is located in its spherical shell, the internal spacetime is flat. Share Improve this answer Solution 1: The event horizon area is the crucial quantity associated with a black hole whereas the volume inside is […]

## Approaching the Event Horizon by Slingshotting Around a Black Hole

According to the first law of black hole thermodynamics, the black hole’s size will expand when the object falls into it, which can be represented by the equation: $$dE = frac{1}{32 pi M} dA$$ Here, the change in energy is denoted by $dE$, and the change in the horizon area of the black hole is […]

## Is the bending of spacetime caused by gravity or is gravity the bending of spacetime?

Assuming two massive bodies are stationary in relation to each other, they would create a bend in space-time, but they shouldn’t be drawn towards each other as they are not moving within the curved space. The question arises as to why an object would fall into the curved space of another object, causing it to […]