Perpetual Motion From Negative Mass?

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With the subject heading: Negative Mass Challenge Question

Challenge question: if 1kg of apples is $5 and 2kg is $10, how much is -1kg of apples? The answer? Priceless. Because you could use negative-mass apples to build warp drives, travel in time, and construct a perpetual motion machine. In fact that last one will be today’s actual challenge question.

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Previous Episode: Why String Theory Is Wrong

Hosted by Matt O'Dowd
Written by Matt O'Dowd
Graphics by Luke Maroldi
Directing by Andrew Kornhaber

Exotic matter – matter with negative mass - has long been the pipedream of science fiction writers, futurists, and certain rather. . . optimistic researchers. It’s the key to faster than light travel because it’s the only stuff that can curve space in the right way to hold open wormholes and construct warp fields. And if you can travel faster than light you can also travel backwards in time. We’ve been over those already. And we also recently covered a very new use for negative mass: as “dark fluid”, a proposed explanation for both dark matter and dark energy. That episode really got me thinking about the subtleties of negative mass and how it should really behave gravitationally. Turns out it’s complicated, and to answer it we really have to question the very definition of mass.

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سلطان الخليفي

[stylz]

Solve the perpetual motion problem and get a free space time t-shirt. HAHA. Love the show.

[lucifer]

I've been watching your videos about 2 years now, I belive. Just wanted to convey my deepest respect and gratitude for your astonishing work. Your channel has the highest production quality of any channel I have seen, as well as the best and constant content, and it's a joy seeing the upload notification from you.
I'm not a physicist, nor a scientist, but over the last two years I have done what I could, practicing maths and studying physics in my spare time, in order to approach at least some of the concepts you present and to try grasp them. It's purely recreational and while much of what you touch upon is still opaque to me, you have aided me in appreciating, at least in some small extent, the miraculous elegance of physics and this noble pursuit of investigating the natural world.
Don't know if you will read this, but I've been meaning to write and say thanks for some time now.
THANK YOU!

[CoolHandAlex]

He's the physics teacher you wish you had in college.

[njdevilsforlifewoohoo]

Can't wait to see the results of this challenge. I don't have an understanding physics well enough to take part, but I do find the subject fascinating.

[NewMessage]

Negative mass apples also sounds like the next big diet food.

[ObjectsInMotion]

Man these videos just keep going and going getting better and better. I can’t stop myself from watching. Keep it up, don’t ever stop!

[kevinba]

"make them the density of a neutron star"

😂😂😂

Better not be under one of those when it falls

[WayneReich]

Can you imagine a world where the spin interaction was flipped so that gravity was spin-1 and electromagnetism was spin-2?

[cleanerben]

1) Get bread
2) butter bread
3) get cat
4) tape bread to the cat's back, buttered side up
5) throw in the air

The buttered side will try to force itself down to the ground. The cat will flip over to land on it's feet. All forces would be equal and the cat bread combo would stay on the air spinning forever.

[evaristegalois]

Negative mass is difficult to achieve ... even Ultra Instinct Shaggy has to use about 5% of his power to create it

[Finnyke]

'Neutron Star Delicious' is my favourite apple variety

[steelgreyed]

This is indeed the breakdown I was asking for, thank you so very much.

[Locuts]

Thought experiment. If negative masses were allowed, would there be a negative mass equivalent to a black hole? Thinking about how masses warp space time in GR I’m thinking of a hill so tall that even a particle traveling at the speed of light with a path aimed directly normal to the hill wouldn’t have enough momentum to reach the peak. The point at which light speed particles could reach on such a hill would have some kind of strange event horizon like quality in that everything “above” this point would be forever out of contact with the rest of the universe.

[archenema]

Thank you for saying you don't know. I don't hear that much these days.

[FrHorrigan]

This stuff is genuinely great. Props to PBS for putting out content like this.

[kylben]

I've always wondered whether mass bends space, or if bent space just looks like mass.

[JungleMan]

Lol...did he say at the risk of getting too technical? Is that something he actually worries about? Lol

[enhydralutra]

3:30 I missed the entire discussion because I couldn't help noticing that the apples spin whichever way you decide you want them to spin.

[markb]

Makes me smile when I see there is a new 1. 😄 this 1 was especially difficult to keep my mind wrapped around.

[edgeeffect]

Oh no!! Now I've watched a video with "perpetual motion" in it's title can you imagine the unmitigated garbage that's about to turn up in my suggestions... I can.