Does Relativistic Speed Increase Gravity Pull?

frujin
Messages
2
Reaction score
0
Hello Guys. I am amateur so please forgive me if the question is irrelevant. As I understood it, the objects moving with relativistic speed, have their mass increased exponentially as the speed increases. Does that mean they have stronger gravity pull also?
 
Physics news on Phys.org
In relativity the source of gravity is the stress energy tensor. It cannot generally be replaced either by relativistic or by invariant mass. Both are scalars, and the stress energy tensor is a rank 2 tensor.
 
Hi, frujin, and welcome to PF!

Your question looks simple, but it actually hides a considerable amount of complexity. Rather than trying to answer it directly at once, let me first explain briefly how General Relativity (GR) describes the "gravity pull" of an object.

The central equation of GR is the Einstein Field Equation (EFE), which can be quickly summarized in the popular phrase "spacetime tells matter how to move, matter tells spacetime how to curve". "Spacetime" in this equation is described by something called the "Einstein tensor", and "matter" is described by something called the "stress-energy tensor" (SET). The "mass" of the object is part of what is described by the SET.

The key thing about this equation is that it is the same regardless of what coordinates you express it in. For example, if some massive object is moving relative to you, the EFE looks the same whether you look at it in coordinates in which you are at rest, or coordinates in which the massive object is at rest. (By "looks the same", I don't mean literally that every number in the equation is the same--I just mean that the structure of the equation is the same, and there is a well-defined way to transform the specific terms in it from any set of coordinates to any other set.)

So in this sense, the "gravity pull" of the massive object doesn't change when you change coordinates. The specific components of the SET will change, so it will look like the "mass" changes if you just look at particular components, but the overall prediction for how objects will move in the gravity field of the object doesn't change.

There are also other ways your question could be interpreted, but I'll let you respond to the above first.
 
Hello, and thanks for the answers. Unfortunately, I can't understand the reasons ;) - mathematics used are quite complex to me, but I am having now the impression that the answer is: the object moving at relativistic speeds won't "gravitationaly attract" other objects any stronger. Is this correct?

But, doesn't the curvature of spacetime around an object increase significantly as its speed approaches speed of light? (sorry of this is redundant question)
 
Thread 'Can this experiment break Lorentz symmetry?'
1. The Big Idea: According to Einstein’s relativity, all motion is relative. You can’t tell if you’re moving at a constant velocity without looking outside. But what if there is a universal “rest frame” (like the old idea of the “ether”)? This experiment tries to find out by looking for tiny, directional differences in how objects move inside a sealed box. 2. How It Works: The Two-Stage Process Imagine a perfectly isolated spacecraft (our lab) moving through space at some unknown speed V...
Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. The Relativator was sold by (as printed) Atomic Laboratories, Inc. 3086 Claremont Ave, Berkeley 5, California , which seems to be a division of Cenco Instruments (Central Scientific Company)... Source: https://www.physicsforums.com/insights/relativator-circular-slide-rule-simulated-with-desmos/ by @robphy
Does the speed of light change in a gravitational field depending on whether the direction of travel is parallel to the field, or perpendicular to the field? And is it the same in both directions at each orientation? This question could be answered experimentally to some degree of accuracy. Experiment design: Place two identical clocks A and B on the circumference of a wheel at opposite ends of the diameter of length L. The wheel is positioned upright, i.e., perpendicular to the ground...
Back
Top