Oh and I got my calc wrong but you got yours too. The neg. mass + normal mass frame, and exerting a force on the normal mass only proves the properties of normal mass and not that of negative mass. The neg mass or mass or whatever within isnt being acted upon so there’s no ‘point’ to the arguement.
Anyway, I just had a thought. IF there WAS negative mass, wouldn’t it have all been shot to the very outsides of the universe first? AND wouldn’t it go faster than light? Big bang occurs - the negative mass is shot backwards (and backwards is still ‘out’ from the origin) - and gravitational forces from other masses ‘pull it back to center’ and ‘slow it down’, wouldnt it just gain more acceleration? to the point of breaking that hypothetical speed limit that is c?
I’m talking nonsense? riiiight… and this is you talking:
The negative matter is not going to ‘fall down’ it’s going to ‘remain in place’. The space ship made of normal matter will accelerate ‘upwards’. ok? And it has 0 inertia, not negative, duh.
Depends on what reference frame you’re using. If you use a reference frame that’s staying with the ship, then the negative matter is, in fact, going to accelerate. And to a person inside that ship, the direction towards the back of the ship feels like down, so it can reasonably be described as “down”. In other words, the negative mass would accelerate downward, just like John said.
And I don’t see how you figure that an object of negative mass would have zero inertia. Inertia is the same thing as mass, so if the mass is negative, then by definition, the inertia is negative.
This exchange is interesting but giving me a headache, and has the Gilbert and Sullivan patter song from Ruddigore running through my head: “matter, matter, matter, matter.”
I just want to impose a reminder from the Moderator: no insults permitted in this forum. Everything has been on the safe side of the line (“what you say is nonsense” is not an insult against the person), and that’s great, I’m just bored this morning so I wanted to remind y’all to keep on that side of the line.
jkim78, you shouldn’t use insults, when you are the one whose background is weakest. Chronos is a physicist, and I have yet to see him make a mistake. I was a physicist, and john has participated in enough discussions that it is clear he has a good physics background, also. I’ll try to explain away some of your confusion.
Inertia, in physics, is not resistence to all change. Inertia is resistence to change in motion. For example, suppose Chronos and I jump off a cliff, and that I weigh twice what Chronos does. Gravity exerts twice the force on me that it does on Chronos, that is why I weigh twice as much. However, we accelerate at the same rate, because my resistance to acceleration is twice that of Chronos, also. Or, if you prefer, my inertia (inertial mass) is twice that of Chronos. The fact that inertial mass and gravitational mass are the same is one of nature’s mysteries called the equivalence principle.
Righteo… your mister einstein… and I’m just some nobody…
and that’s why you contradict yourself. If your not moving, your not resisting anything. See? The inherent resistance inertia ‘will cause’ when it moves doesnt apply because it ISN’T MOVING. So simple and you still fail to comprehend. Like I said before… -1 * 0 = 0. when -1 * 0 = something else, then come back please?
Dunno if this is right or not, but isn’t inertia a property? Whether the mass in question is being moved or not, it retains the property. To say otherwise is like saying that red hair stops being red because the lights are out.
Depends. If you’re not moving you can resist something else that’s moving.
Try this out, pull a tablecloth from underneath a place-setting. If you yank quickly enough, the place-setting will remain on the table due to its inertia. Lo and behold: said place-setting is not moving and its inertia is what keeps it not moving.
Inertia is another name for the quality that all matter (moving or not) has in the low-energy limit. It is also, to some extent, a quality that relativistic particles have, though such is more appropriately expressed in its momentum formalism since there is the little problem of the invariance of the speed of light with respect to reference frames.
It seems to me that you are falling victim to a common “moment” ambiguity problem which is to say that people get the various flux moments confused. I can’t tell you how many people get momentum (the first moment) and kinetic energy (the second moment) confused. They are related in the same way the mean, variance, skew, and kurtosis are related in statistics. No one would claim that the mean and the variance are the same, but for some reason momentum and inertia are hard for some to wrap their minds around.
You are talking about the first moment of mass which is the mass flux (related to the momentum). The others are talking about the zeroeth moment which is simply the inertial mass and does take into account the variant velocity of the frame (at least for massive objects). Thus momentum and inertia as normally defined are not the same thing. An object has inertia whether or not it is moving. An object only has momentum and mass flux when moving.
But the original example in question had that theoretical ‘negative matter’ to be in zero G and presumably in a vacuum with the container of this vacuum moving. If that matter is suspended in a space and the container is moving, then it’s not resisting something else that’s moving either, although I get what you mean, and should change my terminology up there.
If the container is moving then there is no way to tell whether the matter is moving with respect to the container or the container is moving with respect to the matter. Therefore the matter has momentum as well.
