Christmas quiz esp. for astronomers

1. I think the universe itself is infinite so cannot expand or shrink, however the objects within it, according to celebrity physicists are moving further apart relative to each other. The big crash at the other end of the time scale has probably already happened and we'll witness that in a few billions years time.

2. Higgs - He had the force with him!

3. Reindeer walk on dark matter.

1. It only expands into itself, to match its new size.

2. Some would say that was about the only thing left for a god to do, and the only time for it to do so...

3. The ISS is nowhere near good enough. Santa needs a FTL hyperdrive, plus a Stasis Field out of a Larry Niven story, to have any hope of getting around a billion-odd kids in a night. Even at 1 second per child, it'd take him nearly 32 years.

Santa moves by quantum mechanics, thus the probability is that he is everywhere and nowhere at any given time.

The given time seems to be less than a nanosecond after midnight in Dec 25th with allowance given due to the earth's rotation.

If you want to upset your younger relatives, try telling them that it's not so!

I would like to know however, why could he not deliver the kids bikes readily assembled?

* Danny M *

He's too busy with the IKEA stuff!

Geoff

Because he has a social commitment to encourage adult/child communication and co-operation on Christmas morning? :D

Assembling bikes after having consumed the amount of sherries he has on his rounds he probably isn't capable, have you ever tried to assemble anything when you are pissed, I have enough trouble when sober.

Dave W

There is a trick used by Santa - he doesn't deliver everything at the same time. He uses the international date line system which divides the globe (unevenly) so he has a stripe to do every hour. If you look at the Globe you can see which times he has his snap, as there are very few visits to do in some of the Pacific stripes, for instance.

And anyway, the idea that we are travelling through space (or space-time if you insist) is a nonsense, as there is nothing in space so we cannot be said to be travelling through it. All we can say is that we are moving in relation to other objects - stars mainly - but as we can never see the stars as they are now, but only after the light has finally arrived, we cannot be sure about this, either. This is called the uncertainty principle, and it explains why you can never get 100% marks in an exam.

Cheers, Tim

re. 1. Space itself is expanding. There is nothing "outside" of Universe into which it could expand. Lets forget about "Multiverse" explanations relying on so called branes etc. These are unprovable fantasies of current lot of theoretical physicists. They do not have anything more useful to do.

re. 2. God.

re 3. It is related to fungus known as Amanita muscaria, or fly agaric. Laps of Lapland (Norway), from where story of Santa with reindears came, are using this halucinogenic mushroom to gain access to mystic world as per their believes. Reindeers like to consume this mushroom too, maybe for the same reason peoples do. Sensations under influence includes illusions of flying. Active ingreadients of fly agaric are muscimol and ibotenic acid. It also contains toxic and not hallucinogenic muscarine, so large overdoses are best to be avoided.

Martin

There isn't 'nothing' in space! Very little, it is true, relatively few atoms, lots of massless photons, millions of neutrinos etc., but not nothing.

Geoff

@Geoff Theasby,

There is much more - stars, Galaxies etc but we are not talking about objects in space, small or big.

Nevertheless physical space devoid of matter and radiation is sttill not empty. It has positive internal energy to satisfy Heisenberg principle.

It is possibly false vacuum, not really a good news.

Martin

... but please let's not dispense with branes entirely. The bit I rather liked was that two branes got close, "touched" and a bunch of energy was suddenly transferred from one to the other. The rest is history.

I am barking on branes because current models involving them are not open to experimental verification. So they are not falsifiable and therefore not scientific. And should these branes "clap" again, we are most likely fell like if something had struck us with speed of c, hence we would cease to exist without realising what have happened.

But they could exist, who knows?

Martin

Ah, yes, Martin, but even if considering the stars, planets & galaxies in our concept of 'empty' space, do not forget that even the atoms of so-called 'solid matter' are mostly empty space...

Geoff

Ah, yes, Martin, but even if considering the stars, planets & galaxies in our concept of 'empty' space, do not forget that even the atoms of so-called 'solid matter' are mostly empty space...

Geoff

1.) Expanding into obesity.

2.) Someone who broke wind at the wrong moment.

3.) Running on dark matter.

Prove me wrong.

Edited By Mike E. on 16/12/2017 20:45:30

We can follow this path and find that matter is illusion and space is basically empty and all what we know as matter is product of interaction of force fields.

So lets take as an example stellar collapse. At the point of collapse to neutron star our Sun would have size maybe 20km and star about three times its mass would end up with size 10km (this is property of so called degenerate matter - heavier object would be smaller).

Then we cross a line and get collapse to BH or similar object. God only knows what is inside, but there are reasonable suspicions that something known as Planck Star rather than true singularity would be inside - object of density of 10^95kg*m-3.

If you collapsed entire observable Universe (about 10^50kg) to Planck density, it would be approximately of size of bacterial cell. That is all "real" stuff what is around. All features which we observe are just force fields.

Martin

Edited By Martin Dowing on 16/12/2017 21:04:23

Nature abhors a vacuum - and fills it with duplicate posts ....

Neil

Yes, Neil. That's what C.Northcote Parkinson said.

Geoff

1. If there's nothing else out there then there's plenty of room

2. A God, obviously!

3. A rocket motor and Belief! :D