What are the most important questions in science?

What is time? Time is one of the most mysterious concepts in the universe. It seems to exist even when we're not looking at it, and it changes depending on the context. What is its nature? Is it an illusion? A reality? Does it have a beginning or an end?10. What is the meaning of life? This is a big question with no easy answers. Some people believe that the meaning of life is something that comes from within. Others believe that it's something that we create, based on our experiences. Still others believe that the universe has a meaning, and that we can find it by exploring and learning. There's no consensus on what the meaning of life
  • #1

James William Hall

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Summary:: Requesting Your Ranking: https://www.npr.org/sections/13.7/2013/09/10/221019045/the-10-most-important-questions-in-science

In the above https are the ten most important questions in science suggested by NPR--I totally agree. So, my request is, especially from our more qualified members (whom I value highly), please rank the TOP TWO, in your opinion, as being the most important for the human race (and later AI) and our cosmos. If you have time, say why. For those just starting out on your careers--pay attention.
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  • #2
Please list them for your reader's convenience.
You might be able make it a poll, which could do the counting for you also.
  • #3
1. What is the universe made of? We know only 5 percent of the composition of the universe. This 5 percent is made of the familiar atoms of the periodic table, their molecular aggregates or of the components of atoms, protons, electrons and neutrons. There are also neutrinos, the elusive particles that can traverse matter as if nothing were there, including the whole of Earth. The mystery is the other 95 percent, composed of dark matter (roughly at 25 percent) and dark energy (roughly at 70 percent). Dark matter doesn't shine and is found around galaxies and clusters of galaxies, like an invisible cloak. We know it's there because it has mass and hence gravity: It pulls on the familiar 5 percent and we can measure this effect. Dark energy is much more mysterious, a kind of ether-like medium filling up space with the bizarre property of pushing it apart, making galaxies accelerate from one another. We don't know what either dark matter or dark energy are, and there are hypothetical explanations that try to modify Einstein's theory of gravity to accommodate the observations and do away with the darkness.

2. How did life come about? Life appeared on Earth some 3.5 billion years ago, perhaps earlier. The mystery here is how aggregates of nonliving atoms gathered into progressively more complex molecules that eventually became the first living entity, a chemical machine capable of metabolism and reproduction.

3. Are we alone in the universe? This question is really two questions: Does life exist out there and, if so, what fraction of this alien life is complex and intelligent? If intelligent life is not so rare, why haven't we heard from "them" yet? I recommend the book by Lee Billings, Five Billion Years of Solitude, for an up-to-date synopsis of the search for life elsewhere and the key people behind it.

4. What makes us human? We have three times more neurons than a gorilla, but our DNAs are almost identical. Many animals have a rudimentary language, can use tools and recognize themselves in mirrors. So, what is it that differentiates us from them? The thicker frontal cortex? The opposing thumb? The discovery of fire and the ability to cook? Our culture? When did language and toolmaking appear? (Barbara King recently offered her take on this topic.)

5. What is consciousness? We've been there before in these pages, wondering about the nature of consciousness. How is it that the brain generates the self of self, the unique experience that we have of being ... unique? Can the brain be reversed-engineered to be modeled by machines? Or is this a losing proposition? And why is there a consciousness at all? What is its evolutionary purpose, if any?

6. Why do we dream? Even though we spend about a third of our lives sleeping, we still don't know why we dream. Do dreams have an essential function, physiological and or psychological? Or are they simply random images of a brain in partial rest? Was Freud right about his theory that dreams are some sort of expression of repressed desires? Or is that all bogus?

7. Why does matter exist? According to the laws of physics, matter shouldn't exist on its own; each particle of matter, each electron, proton, neutron, should have a companion of antimatter, like twins. So, there should be positrons, antiprotons and antineutrons in abundance. But there aren't. The problem is that when matter and antimatter meet, they disintegrate in a puff of high-energy radiation. If you shook hands with your antimatter other, a good chunk of the United States would blow up in smoke. So, the mystery is what happened to this antimatter. Clearly, if the universe had equal amounts of both earlier on, something happened to favor matter over antimatter. What? Was the universe "born" this way, with a huge asymmetry between matter and antimatter? Maybe some primordial asymmetry evolved to do the job, selecting matter? If so, when did it act in the cosmic history? And what would this asymmetry be?

8. Are there other universes? Or is our universe the only one? Believe it or not, modern theories of cosmology and particle physics predict the existence of other universes, potentially with different properties to our own. Are they there? How would we know, if we could? If we can't confirm this hypothesis, is it still part of science?

9. Where will we put all the carbon? With the global ramping up of industrialization, we are putting more and more carbon up in the atmosphere, accelerating global warming. What can be done to change our impact on the environment? And what happens if we don't? Models of global warming have a range of predictions, from somewhat mild to dire. Should we bet on the low odds that doing nothing will be OK? Or is it time to really take this seriously at a global scale, for the benefit of the next generation?

10. How can we get more energy from the sun? We have based our explosive growth mainly on fossil fuels. Nevertheless, we have a remarkable source of energy up in the sky, waiting to be exploited more efficiently. Also, can we reproduce the solar engine here on Earth, fusing hydrogen into helium in a controllable and viable source of energy, solving our energy problem for the foreseeable future?
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  • #4
in my perceived order of importance.
  • #5
It's very difficult to choose only two from such a list of interesting questions. :smile:
But after some thought, my subjective choice would be

#2, since this is a very interesting question. And the answer to it may also help evaluating the probability of #3.

#9 (though I interpreted it more generally as "What can be done to change our impact on the environment?")
  • #6
They should be in reverse order. 9 and 10 are likely the only questions answerable in anyone’s lifetime
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  • #7
How did the universe begin is number 1 for me. Then how did life begin, your 2
  • #8
I would say 1., which encompasses 7 .
And 9, which for me is more about how much tera-forming and climate control can we actually do, and does solution A, cause problems B and C,...
  • #9
The list is somewhat strange in that #1-8 are all very broad, fundamental questions about the nature of reality that humans have been asking for centuries (if not millennia), and #9 and 10 are quite practical questions grounded in the problems faced in the present day. (That said, I would probably say #9 and #10 are the most important to solve, though I would put #5 at the top of the remaining questions).

In the line of practical scientific questions grounded in the problems faced in the present day, I would propose another important question: "What causes Alzheimer's disease and are there ways to prevent it?"

Here's a nice site describing some of the "Grand Challenge" questions facing cancer research: https://www.cancer.gov/grants-training/grants-funding/cancer-grand-challenges
  • #10
256bits said:
And 9, which for me is more about how much tera-forming and climate control can we actually do, and does solution A, cause problems B and C,...
Concur. Question #9 seems specific to carbon; a possible answer to broader climate control and planetary engineering projects.

Questions 4, 5 & 6: What makes us human, consciousness and dreams; seem closely related. I have read anthropological theories that consciousness defines being human; i.e., homo sapiens the conscious animal. One supposes that understanding any of the three would indicate progress toward solving the other two.

Scientifically classifying and describing dreams, even combined with EEG and MRI data collection and subjective interpretation post-sleep interviews, remains a nightmare (pun partially intended).
  • #11
3. Are we alone in the universe? This might easily become far more important than all of the other questions put together if we find out we're not.

Why have we not heard from them? The age of radio has lasted a little over 100 years on earth. That is just a tiny fraction of the time humans have existed. And even now planet Earth is heading towards radio silence. Looking for radio signals from distant civilizations is likely looking for a flash in the pan.

The question also presumes we have not been visited. And that is certainly questionable given that almost every ancient culture had legends and myths claiming we have been visited. Some cultures still consider that to be a matter of history, not myth. It is logically unjustified to claim as fact we have never been visited.

I find it especially amusing when based on nothing but assumptions, people who claim to have seen an alien spaceship are tagged as crackpots or nuts by the same people who also ask, why have we not been visited.
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