In this week's questions show, I explain why you could have a steam-powered rocket, how often spacecraft have crashed into asteroids and comets, and why a red supergiant star actually has a very low surface gravity.

02:42 Could you build a steam-powered rocket?

04:48 Have any probes crashed into asteroids or comets?

06:47 Surface gravity of UY Scuti

08:57 Will we ever send humans to the surface of Venus?

11:08 Lol

11:24 Does Venus have a magnetic field?

12:22 Longer guest interviews?

14:09 Save the shoutouts to the end

15:55 Could a probe float at the surface of Venus?

16:47 Where do I get my news?

20:29 Why don't meteor showers hit satellites?

21:57 Why not add a module to James Webb?

Want to be part of the questions show? Ask a short question on any video on my channel. I gather a bunch up each week, and answer them here.

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Hi Emma. Not in any way putting you down, but the internet is chock-full of cranks claiming they have developed a theory of this or that, and that their theory is truly a ‘theory of everything’, but the mainstream scientists refuse to take their work seriously because they’re afraid of being shown up etc. etc.

The thing is, it’s the easiest thing in the world to come up with a hand-waving qualitative explanation of what one thinks may cause gravity (or something else), but the ultimate arbiter of truth in science is the process of quantitative comparison of the predictions of a given theory to hard and fast empirical experimental results.

The problem with this guys ‘theory’ as it sits on his website is that it has zero explanatory power, and hence makes zero solid predictions that could ever be tested. Accordingly, it cannot be classed even as scientific, let alone a candidate for the unification of gravity with the other known forces…

ok i see your point, but just for my own education as im not that well clued up, do you see anything in his theory that you think could not ever possibly be true and why?

This was one of my favorite podcasts so far! Keep working towards that Nobel prize!

@emma:

Maybe, but thats not the point. There are many ways to explain the universe. But thats not science. Science is to create a model/theory that makes predictions. With these predictions you can verify or falsify this theory.

All “verified” and “accepted” theories are still just models and not the reality itself. we will never be able to see for example an electron our selves. but even if we could, how can we be sure that it is really there … just … like …. The Matrix. Ok i dont want to say that our world is just an simulated environment, but i think you get the point!?

there can’t be equations and answers for EVERYTHING– you can have theories but thats all they are, theories. Personally, I believe that when God created the universe and everything in it he made some laws and phenomena just for fun, because He wanted to, for His glory. and, personally, i believe that He made some things unexplainable scientifically, just to show us that He is in control, that even if we don’t understand it, He knows what’s going on…

God or not, I know the world would be a better place if everyone would stop talking about his/her God.

Emma,

None of what he says makes sense.

If gravity was a ‘push’ then gravity wouldn’t be affected by the distance away from an object. It would be the same whether you were on the surface or 10 light years. Also, if everything had a push relationship, objects would repel each other.

His space time fabric is a really bad twisting of how Einsteins example of gravity and its affect of space time. Mr. Lees states the space time fabric exists in one plane with layers; based on the movements of galaxies througout the universe, and the fact gravitational lensing is a fact, this is obviously not the case. Space time fabric can exist in different planes at any angle.

His theory on gravity and the atom is a twisting of how the Higgs field works. He seems to like to take current theories and change them up qute a bit without proof or good examples. Such things as simply dismissing the graviton without any explanation isn’t science, its fiction.

Another item here, if space time plane was held up by the proton, then the plane would actually interfere with the movement of electrons. Both within the atom and from jumping between atoms; thus interfering with both the weak force and the EM force… again, not the case.

Gravity and the moon.. if this was true, then the tide wouldn’t be a single bulge of water on opposite hemispheres, it would be two bulges separated by his gravitational push force in the same hemisphere; also, there would be no offset on where the actual tide takes place and the location of the moon.. but there is due to the Earth’s rotation.

Although we may not know what exactly everything is, you can work through what something is not.

Aodhhan – an excellent post.

thank you Aodhhan, your post helped me a lot

This is not real mathematics and I don’t pretend to understand the audio I listened to but this is what I think I heard…

Unified field theory attempts to explain observable phenomena such as symmetric known and predicted particles and such created by high energy colliders and takes us back to ground zero of the creation of the solar system and then maybe some even attempt to extrapolate back to and even before the big bang .

We postulate and hope the existence of the higgs particle and others because it would make a nice tidy happy symmetric family with no errant bad unruly non symmetric particles , and would perhaps explain all the known laws of physics , strong and weak nuclear forces etc.

We see different states at different discrete units of time starting a time zero wheras in reality it is a continuous function to be dealt with.

From just one unified state , All of these forces eventually appear at lower and lower energy levels until we get to where a steady state existed after some time.

Why not attempt to solve this puzzle !

From what I heard …..

The partial differential equations describing the gravitational and the one describing the electromagnetic force appear the same only at high energy levels …

My question is how sure are they about the accuracy of these equations in describing the observations ? based on the snap shots of all the known things we have glimpsed to date .

Aren’t the equations just approximations ? , and if so incompleteness is apparent in alot of what is dissussed and it is not based on rigorous mathematics ,,, it is hopeful thinking and perhaps neither Einstein or anyone except God perhaps (please pardon the phrase) can percieve it all.

I think as one article I recently read stated , that the universe may be mathematics or be 100 % describable by PURE mathematics and most of it undetectable by humans .

Maybe it is solvable from a higher form of mathematics in higher dimensions of observation and what we observe is a shadow from that dimension like the super cube down to the cube down to the square etc.

In mathematics it was Galois who discovered (or invented) a higher level …Group theory ,

and used it as a tool to solve the quintic equation conjecture i.e there can not be a general solution for finding the roots for any fifth degree polynomial . which is solving a lower level problem from a pure or higher level.

As she said in the audio she hopes for a young genius to appear and look at it from a higher level and produce the higher mathematics which develops the grand theory.

and enables us to understand the “shadow” observations we are fortunate to observe with our low level of available senses and brainpower .

Maybe string theory is the higher level we need to go to even though there are no physical evidence for it.

There is no harm in trying no matter the approach and it is an interesting applied problem of great value to science and physics.

String theory may be a waste of time since it has been around since the 70’s and no proof of evidence in the real world.

Lee Smolin thinks it may be a dog which won’t hunt and a waste of time .

But many hard problems in mathematics have been solved from a higher pure level like that as by Galois mentioned above

Another For example :

Gauss refused to spend time on proving Fermat;s last theorem X^n + Y^n = Z^n has no solution for X,Y,Z integers and n > 2 .

because he could see no real world value in its solution and one could spend a lifetime in trying to crack that nut and it might be futile he thought .

Many thought it was insolvable after Godel proved his incompleteness theorem in 1932 which proved that there are an infinite number of True conjectures which can have no possible proof in the field of arithmetic .. but nevertheless they are true.

So , since mathematicians had been trying for 300 years to solve Fermat’s last theorem to no avail they thought that was one of Godel’s True but not ever provable ones.

There are infinitly many True conjectures but the majority are in the class of unprovable ever.

Fortunatly Andrew Wile proved Fermat’s last theorem in 1994 by using the works of many mathematicians including Galois, Sophie Germain , Taniyama and the connection between Modular Forms and Elliptical Functions (Taniyama Conjecture) and over 400 pages of pure mahematics.

The approach was proving Taniyama conjecture proves Fermat’s last Theorem and vice versa.

Look it up in wikopedia or google it.

The point is most of all the true conjectures in the universe of mathematics are never provable …by Godel’s theorem … so just maybe there is a analogous Godel’s Theorem in the field of physics and our universe as well and if that person is correct in stating that the Universe = Mathematics …then it figures.

In that case , we can never understand the mind of God(el) however much we try and resistance is futile….

Godel ruined the works of many famous mathematicians like Hilbert , and they were horrified when they realized their worst nightmare had come true … there are true theorems which are unprovable.

Maybe God things in our universe from a higher level universe viewpoint and we cant since we are in our universe and are part of it and unfortunately cant observe from a higher level.

We can try but should not be humiliated if we cant san’t solve the unified field theory because we are not Godel and are only part of the universe .. we are only partial observers and can neither understand the universe completely or even see it completely.

Please note… I tried to not mention God but you can look on the word as merly an expression of the whole iceberg rather than just the tip of what we are capable of understanding or as the total truth in the universe as compared to what we have the power to prove or even see for that matter.

This may deflate our egos but since I am only one insignificant creature in this universe how could I expect to understand it all from within it.

Fantastic posts from all, best read I’ve had all day, and well said Elminster.