Senate What are the greatest mysteries in science?

I think its how you define "makes up" that effects this. If you're just talking about matter, then dark matter would be the lion's share of what's in the universe. Though, its not really 'the world around us', as the world around as, as we perceive it, is entirely material that wouldn't really be considered dark matter.

The dark energy number is, i believe, when you look at energy in the universe plus rest energies of matter. But I'd need to double check that.

 

A question, if you don't mind... what exactly is the scientific consensus on what the difference is between matter and energy? Einstein proved they are convertible. We've been able to convert small bits of matter into huge pursts of energy. I've also read we succeeded in creating matter out of "nothing" but absolutely pure energy. Both matter and energy are made up of the same fundamental particles. When studying atomic structure in chemistry, it seemed like electrons "absorbed" or "emitted" photons, which would change their energy level and electron orbital, which seems to indicate that electrons are composed of photons (yet the Standard Model says electrons are fundamental leptons, like I put above).

I've always been slightly confused by it.

 

I don't see how absorbing and emitting photons indicates that electrons are made of photons.

(Lowbacca, correct me at any point if I'm wrong)

The electron cannot be made up of photons. An electron has a charge of -1. Photons have no charge. So i don't see how they would be made up of photons.

When the electron absorbs a photon, it absorbs the energy. Since a photon is massless, it is all Kinetic Energy. When the energy is absorbed, no more photon. The photon doesn't go inside the electron in the way we think things do.

 

Vivec has it pretty much spot on. We go too far down this road and I'll have to go dig up my particle physics text, as its been a couple of years since I took it, but on the level of particle physics, you really do have particles going in and out of existence so long as you have basic conversions. conversion of energy (in this context, then, we also talk about particles having a rest energy, roughly the E=mc^2 concept), conservation of charge, conservation of momentum and angular momentum, and a couple others. So for a reaction to work, the sums for each of those can't change.

For example, neutrinos were predicted before being discovered specifically because as we were observing at the time, conservation laws were being violated and so they predicted an as yet undetected particle that, when included, maintained conservation of energy and momentum.

In a nutshell, particle physics is weird.

 

Yeah, I still don't completely understand, but I doubt I ever will. A photon is a fundamental particle, yet it can pop in and out of existence. I get energy and fundamental forces being made out of particles, but that's not how they seem to behave. Quantum physics is weird.

Moving on, how likely does it seem that we'll find a "theory of everything" that breaks down all matter, energy, the four fundamental forces, mass and the Higgs boson, dark matter, dark energy, and antimatter into a single set of mathematical formulations?

Does M-theory (string theory) or Loop Quantum Gravity Theory seem more likely, or do you think it will be something completely different?

http://en.wikipedia.org/wiki/M-theory_(simplified_explanation)

http://en.wikipedia.org/wiki/Quantum_loop_theory

The main problem seems to be reconciling Einstein's spacetime/gravity with Plank's quantum particles.

Many people seem like like String theory, and I do like how beautifully simple it seems with all partciles being different modes of vibration of a string, but making up other dimensions just for it to work seems like stretching it.

LQG theory, on the other hand, needs only the known dimensions. It says that the fabric of spacetime itself can be quantinized as being weaved of quantum loops.

I think it is likely to be a combination of the two. That all of spacetime and matter/energy are made of the same stuff, the same fabric, but matter/energy are just vibrations within the fabric and made of the fabric. I don't know, I'm no particle physicist, that probably sounds like nonsense!

 

I know you're moving on, but forgive me, I may have a way of explaining this (As usual, Lowbacca, if you see me screw up just let me know).

When you go into Quantum Mechanics, you have to let go of macroscopic definitions of certain words. Behavior on the level of human interactions is fundamentally different than that of the quantum scale.

The "popping in and out of existence" occurs because the photon is all kinetic energy. It has no mass. That being said, when the energy is absorbed, the electrons energy state is increased. So the photons are no longer photons because they are now the energy in the excited electron. Once the electron goes down an energy state, the energy is released as a photon. So did it go out of existence? To us in the macroscopic world, perhaps. But since the photon is kinetic energy, and the kinetic energy was transferred into internal energy, and then re-released as kinetic energy, it didn't really "disappear." It seems weird to us because we don't have non-negligible macroscopic quantum interactions in our everyday life, but when you look at quantum mechanics, you have to let go of it being weird.

The negative thing about it is that all other modern physics from Quantum Field theory to high energy physics to even modern electronics requires an understanding of Quantum mechanics, making this the biggest hurdle one must go through to get into modern physics.

 

Then why is a photon called a particle if it is just energy? Are all particles really just energy, or just bosons?

If all the energy, all the photons, were to leave an electron, would the electron still exist? If the electron no longer exists, it would seem like an electron is just a bundling of pockets of energy (photons), and whatever it is that does give mass (the Higgs boson?), and not really its own fundamental particle.

Also, since the electromagnetic force and the weak nucelar force have been "unified" into the electroweak force, does that mean that W+, W-, and Z bosons are photons? (that way this discussion can lead into discussion of the TOE's)

Sorry about all the questions, just curious.

 

It is called a particle because in some situations is exhibits particle-like behavior. It is also called a wave because it exhibits wave-like behavior. Remember, fundamental particles are not just "particles." They're also waves. It is called Wave-Particle Duality and it is one of the corner-stones of Quantum Mechanics.

Not all particles are all energy. All massless particles are all energy, though.

I don't see how all the energy can leave an electron. Even at the lowest energy state, n=1, the electron has energy, mass, charge, etc. So therefore I don't know how to answer your question on that.

As for the W+. W-, and Z bosons, I'm sorry, but I have not covered the topics yet. So I'm afraid I can't answer the question.

 

I'm going to agree with those who said earlier that dark matter and dark energy are the universe's current most intriguing scientific mysteries.

First, we believed that the Earth was the center of everything.

Then, we believed that the Sun was the center of everything.

Then, we debated whether the Milky Way was all of existence, or if the "Andromeda Nebula" was just as large as and separate from the MW.

Now, we realize that the visible universe is a relatively inconsequential minority of the larger whole, not only because the universe beyond our view is predicted to be larger in scale to our visible universe than the visible universe is to our solar system, but because dark matter and dark energy make up the vast, vast majority of all mass, visible or not.

If the question we are looking to ask is, "Why is there something instead of nothing?", then perhaps we best understand what most of that something is.

It's so intriguing.

 

I'd have to say the subject of life on other astronomical bodies and it's nature.

Given raw statistics and the shear number of life capable stars out there, it seems obvious that something must be out there, but I wouldn't mind some solid empirical evidence. Not to mention I'm curious as to how life could develop on a planet besides our own, especially given our already rather diverse biosphere. Would parallels exist? Would we see things we never thought we'd see? Would (or will) the discovery of life outside of our biosphere cause a massive paradigm shift?

I find it all fascinating, which is ironic, since I'm not a biologist.

 

I think that life exists out there, but just hasn't progressed in the same way we have.

We may be searching for the wrong thing when we search for life. I always wondered if life exists on other planets, but does not exhibit what we look for, and traditionally think, that life should portray, then is it life?

What if we found fossils on other planets, what calamity would that cause?

Also, what classifies as "intelligent" life? Are we expecting to find a humanoid race or just bacteria?

-KB-

 

That is certainly a good question. I think it would end up in the realm of neurobiology, psychology, and philosophy. I'm not in any of those fields, but I'd like to take a stab at this.

Most attempts at setting some form of criteria for determining whether anything is intelligent or not will start never ending debates. But I do think that there is a way. If we find bacteria, well we know that's not intelligent life. But if we find a species that is semi capable of understanding how it's surroundings works (science) and is capable of manipulation of said environment (engineering), then we've stumbled on "intelligent life."

I could be wrong though.

 

How do we even know that we would recognize something as "living" when we find it? If there's no way to communicate, we could mistake life for some other srange natural phenomenon.

I very much doubt that alien life would have DNA, or that it would be carbon-based or water-based. I doubt even more that we'll ever find other humanoid life, or even Earth-like bacteria. I think there is life, but most of it must be completely alien to us.

 

You are probably right on that, Ghost. Hollywood humanizes aliens, giving them physical, emotional, and mental traits they would probably not even have. Most likely any intelligent alien life would be very, very alien.

 

There was a great show about plausible alien life on the Discovery Channel a few years back. it was a pseudo-documentary akin to the Walking with Dino shows.

Alien life is likely, as you said, very different from us.

 

I would say the greatest mysteries would be on the extreme macroscopic scale black holes bending the fabric of space-time, and extreme nanoscopic scale with whatever the heck electrons, protons and neutrons are made of.

 

Protons and neutrons are made of quarks bounded by gluons.

 

only a model.

spherical chickens in a vacuum etc etc

 

What?

Do explain.

 

I'm going with time's arrow for the "greatest mystery in science". Why does time only seem to go one way? There is no physical reason for time to only go this way; it just does.

 

you've never heard of spherical chickens in a vacuum ???

 

I've heard the joke. What science guy hasn't?


I thought you were implying that Quantum Mechanics wasn't real, which kinda got me confused.

 

No no, I'm definitely not suggesting that quantum mechanics aren't 'real', more that to explore and examine sub-atomic particles requires some crazy machinery and hence it becomes almost impossible to transfer into every day observations.

One of the issues with using quantum mechanics is that the original theories have been proven with complex experimentation and occasionally relying on assumptions about conditions. You can tell (most) people that the world is round and they'll agree. However, many people take convincing that the exploration of the models of subatomic particles is 'real' because you cannot see it (nor it's effects directly).

Sorry, my post is a bit of a ramble, hopefully you see what I'm saying.

 

True. I'm just getting into the more advanced Quantum Mechanics in college, and I can certainly agree with that.

Yeah. I understand what you're saying.

It's difficult to explain things that don't follow the rules of the macroscopic world because people have difficulty letting go of the assumptions that come with living in a macroscopic world.

 

Pharmacology (my background) is the study of chemical interactions that you cannot 'see'. However, it's extremely straight forward to observe the physiological consequences of drug-receptor interactions which makes for an easy 'observational' science.

You can't "see" the interaction of adrenaline with adreno-receptors, but you certainly can measure changes in heart-rate and blood pressure.

We get as far as chemical interactions - mostly why slight changes in the chemical structure of small molecules leads to dramatic changes in observed physiology ('small' to us is less than 500 of a molecular weight). That's about as close to subatomic physics as I'll ever get.