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sshort75
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If this question has an answer I didn't find it on the rest of the forums.
haael said:Negative total mass (energy) is possible, but it is perfectly equivalent to positive mass with reversed momentum direction.
This isn't correct. Yes you can flip the signs of any or all of the variables that appear squared in that equality without violating the equality, but you will run into a bunch of problems with such things as conservation of momentum in particle collsions and Newtonian gravity (as Jesse already mentioned).haael said:Total mass and momentum 3-vector together form a 4-vector called 4-momentum. Total mass is its time component. Rest mass is its length. Of course this 4-vector lives in Minkowski spacetime, so total mass and rest mass are related by a known equation:
[tex]m_t = m_0 / \sqrt{1 - v^2/c^2}[/tex]
In natural units ([tex]c = 1[/tex]), the rest mass can be expressed as a length of 4-momentum:
[tex]m_0^2 = m_t^2 - p_x^2 - p_y^2 - p_z^2[/tex]
Consider a particle with some positive total mass and some momentum. This particle would have some rest mass and it would travel by some trajectory.
Now consider a particle with the mass and momentum reversed, i.e. negative, but otherwise the same that the previous particle. This second thingie would have the same rest mass and the same trajectory.
There is. A positron is exactly like an electron but with a positive charge instead of a negative charge. In particular, they have exactly the same mass.sshort75 said:Thankyou very much for the answers I should of phrased my question better I was wondering if antimatter had a weight of less than zero. I knew that it was magnetically attracted to matter because of the charge but I did not know if gravity repulsed it. It is my understanding by researching the topic further that there is no conclusive evidence one war or the other.
haael said:Philosophically, negative total mass describes particles that move backwards in time.
Antimatter is a type of matter that has the same properties as normal matter, except for the opposite electrical charge. For example, an antiproton has a negative charge while a proton has a positive charge.
No, antimatter does not have a negative mass. It has the same mass as normal matter, but with opposite charge. This means that when antimatter and matter collide, they annihilate each other and release a large amount of energy.
Yes, scientists have been able to create small amounts of antimatter in laboratory experiments. However, it is extremely difficult and expensive to produce and store antimatter, so it is not currently produced on a large scale.
Antimatter is important in scientific research because it helps us understand the fundamental laws of physics. It is also used in medical imaging and cancer treatments, as well as in spacecraft propulsion.
While it is theoretically possible to use antimatter as a source of energy, it is currently not feasible due to the high cost and difficulty of producing and storing it. It would also require significant advancements in technology to harness the energy released from antimatter annihilation.