What is mass? and is negative matter really possible

[anj16]

what is mass? and is negative matter really possible

i wasnt sure if i should post it in this forum or not but i thought the second part of the title refers to particle physics so i posted this here.

so as the title suggests i was wondering what is mass. i have heard answeres like it is a property of matter, etc, etc. But i am still not convinced as to what mass really is. i was hoping someone here would be able to give me a convincing answer.

and my second question :
can negative matter really exist when looking at the "there elementry particles" and there properties in this sort of universe?
p.s. please do not confuse negative matter with antimatter as a lot of people does.

i am hoping for some good convincing answeres
thnx

 

[Drakkith]

Mass is a fundamental property of matter. It is what causes an object to resist acceleration. Hit up wikipedia and search for mass to see more info on this. Also, do NOT think that science simply "doesn't know what mass is". We know exactly what it is. What we don't know is the exact process that causes it. That is one reason we are searching for the Higgs particle.

For your 2nd question, there is no evidence that negative mass exists and no reason to believe that it might.

 

[Disinterred]

To answer "is negative matter really possible?" you would first have to define what you mean by negative matter.

 

[anj16]

so drakkith y would a body want to resist acceleration anywayz if there is no opposing force??
for instance let's say there is a spaceship in space and if u fire the ion engine it will just move in a particular direction, and there is no gravity in space so there is no force opposing or holding the spaceship back so why would it resist acceleration?

 

[WannabeNewton]

In order to accelerate it you first need to apply a force and mass can be a measure of how much it can resist that force i.e. F = ma.

 

[Drakkith]

Sorry, I think I explained it incorrectly. Mass causes an object to accelerate less when a force is applied. IE something with more mass accelerates less than a less massive object does when an equal force is applied to both.

 

[Studiot]

There is a property, known as effective mass, that can be postive or negative.

When it is negative a Force does indeed accelerate the effective mass in the opposite direction to positive mass. This can be seen in the Hall effect in semiconductors.

http://en.wikipedia.org/wiki/Effective_mass_(solid-state_physics )

 

[jacobadam]

Mass is how heavy something is without gravity.Another way of describing mass is:Mass is how much matter an object has. Mass is measured in grams (g) or kilograms (kg)

 

[l470594464]

Now none of the theories include negative mass so if negative mass exists, there must be new theories.who cares.Let's wait for it.