Dark Matter = Negative mass?

We all know that from the theory of general and special relativity that gravity is just an illusion that a body undergoes when it travels through the fabric of space-time, creating simultaneous depressions, that causes other bodies to be attracted to it.

But, just as a thought experiment, if we compare the force of gravity to one of the other fundamental forces, i.e. the Electro-Magnetic force, we try to think of a kind of a repulsive gravity. My questions it that, could Dark matter, or whatever that is trying to expand our universe be an example of this theory? I mean, could there be negative mass, and I don't means stuff like $-5 kg$ . That's irrelevant.

What I want to ask, is if there's something that does all the work and has the same properties of ordinary mass, but repels? I have heard and watched a couple of vids on this topic, and this really is kind of interesting...(for me, at least! :P).

Please share your comments and reviews to this theory.

#Mechanics

Easy Math Editor

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Comments

@Abhineet Nayyar @Kalpak Shukla What is the probability that negative mass IS dark matter? Could negative mass be claculated via gravitational lensing?

Hilary Sackett - 4 years ago

Hmm, this really IS interesting. I do not consider myself to know anything about space time, So I'll just apply basic Physics here.

So, the fact that this COULD be true has an explanation which goes something like this:

How can space time expand? Imagine spacetime to be a rectangle. Divide it into two parts. Let one be the Dark mass and one be the Non-dark mass and other stuff. Dark Mass : Non dark mass <1

So, one possible expansion reason is that the Dark mass part pushes away the other part,i.e. it repels.

So this does prove that a negative mass exists.

Second is that dark mass may have this property to just Push itself out so that the universe expands.

So, both explanations are possible.

Now we wait unless someone who has immense knowledge on the subject sheds some light on the topic :P

Mehul Arora - 5 years, 3 months ago

But wait a second....how do we even know that it is indeed dark matter that causes expansion? I mean we can just see the results and not the causes, can we?

Moreover, even if we could...what would you view as the properties of this negative mass...?

A Former Brilliant Member - 5 years, 3 months ago

Well yes. All I'm saying, that if it does, It IS a theoretical possibility.

Mehul Arora - 5 years, 3 months ago

@Mehul Arora – The part where people get confused is when it comes to dark matter and dark energy. Dark matter has nothing to do with the expansion of our universe! Dark energy is what is the reason for the expansion of our universe and also is considered to be 70% of what our universe is made. Negative mass is not a possibility because mass is defined as the amount of matter in a particular volume (and no antimatter does not mean matter having negative mass). The term "Dark matter" does not mean that it is somehow opposite of matter. It is termed so as it had gravitational properties and had mass but is not visible by any other means except for the gravitational lensing that it creates.

Kalpak Shukla - 5 years, 3 months ago

@Kalpak Shukla – The way you defined mass is quite a basic definition. According to relativity, mass is that property of a body which causes gravitational interaction between two bodies. And that, my friend does bring out the possibility of negative mass. It's so hard to comprehend by everyone, because no one expects mass to be negative, but it can be.

The reason we haven't found it is what you just stated, "DARK MATTER DOESN'T INTERACT LIKE ORDINARY MATTER".

A Former Brilliant Member - 5 years, 3 months ago

@A Former Brilliant Member – What I am trying to say is 1 - expansion of the universe is due to what we call dark energy not dark matter. 2 - dark matter exhibits nature like normal matter in the case of having gravitational force (which inturn gives Galaxies its structure) and does have positive value of mass as seen in the effect of gravitational lensing which is similar to the results we see in normal matter's (I.e. stars,etc) case. 3 - Existance of negative mass is a hypothesis as of now and it differs in its properties as hypothesised from dark matter.