Life Definition and 965 Threads

Are there any papers describing the possibility of life on Ganymede? I understand it is believed to have a liquid water ocean. But few seem as excited about Ganymede as they are about Europa. Is this becuase of the location of the ocean? If there are few or no prospects for lilfe on Ganymede...

I choose this site because it displays the pictures, but the article is hitting all the news sites: http://yourtubenews.ning.com/forum/topics/life-spotted-on-venus-russian-scientist Considering extreme life does exist on Earth is it possible that it does exist on Venus. After all the thick...

When i get some money that i wanted a want more. When i get some respect that i wanted a want more. It seems same thing is with power. Every time i want more and more and it never stops, where is the limit? And what is a real meaning of life? I'm sure it is not about running to delight all my life.

When i get some money that i wanted a want more. When i get some respect that i wanted a want more. It seems same thing is with power. Every time i want more and more and it never stops, where is the limit? And what is a real meaning of life? I'm sure it is not about running to delight all my life.

I read this very interesting article on physorg about how planetary tilt is essential to life and various things that can diminish axial tilt over time or not give rise to one; things that would make life less probable. But I came across this quote that I couldn't help but question the accuracy...

There has been some discussion about whether the methane lakes on Titan could harbor life. What I haven't seen discussed is the potential for life in Earth's methane lakes. There are many underground reservoir's on Earth that contain light hydrocarbons such as methane. If I'm not mistaken...

Hello everyone, First to preface I am not a scientist and have the heart of one (I purchased the heart from eBay... jk). Anyway I have a lingering question regarding Europa: Ok, I get the science about the tidal forces on Europa that flexes the rocky portion of Europa heating up the...

Does this actually happen in outer space? Do things actually move in uniform motion relative to each other? How would this work for the Earth considering it's rotating? Can the Earth ever be considered an inertial frame because it's always rotating?

I am getting my BS soon, I'm okay with going on to get my Masters if I want to do Medical Physics, but I'm not too keen on getting a PhD. I do not want a teaching job. Can anyone explain life after college to me if you want a job not in teaching or grad school? I'm pretty clueless.

It might just be finals getting to me, but what else can I do with a Bio degree besides med school and teach (which I don't really want to do)? I was thinking about it and it seems like a Chem or Biochem degree is way more valuable to industry? I'm sure (hoping) it's not true and I think I'm...

I have no idea where this topic belongs since it combines physics and biology. Is there a way to describe life, growth, and evolution in terms of Atoms or Physics. Or are they two completely different things?

Can you use any of these theories in daily life? Or how can you?

Hey everyone, I recently got a job tutoring a High School student in physics. I'm in fourth year at university. I've just had my first session, and I quite enjoyed it. Though I'm now very nervous about my student's upcoming test. I'd like to give some interesting physics related...

Homework Statement The radioactive nuclides released into the atmosphere by the Chernobyl nuclear accident in 1986 included both 131I (t 1/2= 8 days) and 137Cs (t 1/2= 30 years). Given that 5 times as many 137 Cs as 131 I are present in the reactor in steady state, and that 131 I is produced in...

My question is based around the subject of quantum processes. Is it possible that every living thing is a probable outcome of the original spark or energy. thus saying that every other living thing is a different version of myself. just a thought

If someone in a distant stars is watching for signals of life coming from other planets, how far did the signal of life in Earth travel yet, in a cosmological context?

I'm doing a research project which aims to develop a mathematical correlation for fatigue life prediction at resonance frequency. An experimental setup is also to be created which would be used to carry out the experiment, cyclic loading cycles until failure. For this a Cussons linear vibrator...

Homework Statement This is mostly a statics problem but I'm sure this forum can help me out. Mostly all in the picture. I am trying to find the force in the x direction at point B resulting from loads P1 and P2 at point A. Point A is at the center of the cross bar so therefore it is at equal...

I have been trying to maximize the life time of my laptop battery. My approach to that is to almost use up the charge in the battery then immediately charge it. It is always annoying when the battery have 5% left, because that's when it hibernates automatically. Can I change the settings so it...

my previous post about using nuclear power to travel near or at the speed of light was solely inspired by gleise581g. this system being relatively close at 20.5 LY away, which with current propulsion technology would take around 300,000 Earth years to travel there. although this extrasolar...

Hi, There have been many excellent posts recently about entropy in the universe ... some I've understood more that others. So, I have a fairly basic (I think) question: following the standard comosological model, has the (estimated) measure of entropy in the universe increased over it's life? To...

Hi All. Recently I came across pretty interesting description of life, which was positioned as ultimate truth, and the funniest thing is that concerning it's strictness and at the same time generality it looks like pretty probable candidate. I wonder what do you think about it, can it stand...

The possibility of life on other planets has been one of our oldest doubts... and oldest hopes. Many believe that we are the only ones here in an infinite and lonely universe, but, as put so eloquently by in the film Contact, based on the novel by Carl Sagan, "If it is just us, it seems like an...

Can you give me some "real life" examples of simultaneity? For instance I know the one about the train and the lighting strikes but I was under the impression that this only holds up if the train is moving close to the speed of light. Thanks.

Hey, so here's my story: I've always been incredibly interested in theoretical physics and math. I was never really exposed to it as much as other kids in my high school, though, and so we had some ridiculously good math students. I quit being competitive in math/physics ever since a bunch of...

Is it just that you create your own meaning or is it there is no meaning or a different options? Also if everything is predetermined does that change the meaning of life? I would assume it would make no difference to the answer.

Homework Statement I'm not sure if whether mass changes when atoms decay. Does emitting alpha/beta/gamma cause the atoms to lose mass? I don't know :confused:Homework Equations Uranium-235 has a half life of 7.35x10^5 years and uranium 238 has a half life of 4.5x10^6 years. Compare the two...

a lot of people are trying to prove its real. I am a noob at quantum physics but I've been reading up a lot about it.I took physics in high school and did really well but this quantum consciousness idea is driving me crazy. Can someone tell me exactly why quantum consciousness isn't true...

Universe created with an explosion. ie, work directly propotional to energy. after the explosion of a universe get gravitised. ie, work directly propotional to force. there fore equation would be work=constant*energy*force Can there be a fixed value for this constant if yes what is it...

Oks, I've always been a passive reader of forum...Until now =) Im a ME student, finishing my 2nd year AND I am working 20hours/week at a well renown technology institue at my country. Working only 20hours per week gives enough time to study, so I am doing ok. Yesterday, another job was offered...

Hello everyone, I am in my fourth year of University and still have no idea what I want to do. I completed the first year of Engineering last year, but I did not get into Electrical because my average was just over the minimum required and all the people with better averages got in. I like...

Life on Earth has existed for around 3 - 4 billion years and Earth itself has been around for about 4.5 billion years. I personally believe that there is intelligent life beyond our home planet, I think it is probably quite abundant given the numbers of stars and planets that are out there...

...or maybe not a definite "no", but a positive "much more rare than scientists predict". I have been pondering this question, and every scientist I hear speak on the matter does the famous "alien life equation". What they fail to do is factor in a few variables along with how many planets...

Is the universe similar to Conways game of life? Let me elaborate. For us, a second is the unit of time and its a pretty short unit of time. But then at the atomic scale, a second is a pretty big unit of time. Everything we do is in the order of seconds or maybe milliseconds. But so much happens...

Hello Folks, I have an interesting question (I think)... how far back in the history of universe would you have to go before any form of life existed? Thanks. CJ

Homework Statement Electric motor in put power rating is 17.5kw Voltage is 48V Battery is 7.5kw/h Average W needed to maintain motor per sec is 1446.7W Homework Equations Motor: W=I*V > I = 364.58Amps The Attempt at a Solution My attempt: If 1kw = 3.6 x10^6J > 7.5 * 3.6 x 10^6 =...

Yes, I know that it should be found and hunted (harvested?) first. ;) Let's take assumption that's a carbon based life form using water as solvent. Are the aminoacids that we use the only feasible and convergent evolution would cause that they would have the same? What would be a reaction...

Hello everyone, I recently found this site PhysicsForums and hope I can find some help from it. I've written a 6600 word essay on everything I learn from the Universe using youtube. I did it just for my own knowledge, how and why things work the way they do. I'm in grade 11 and almost going into...

I'm starting my PhD a few weeks from now. I'm just wondering if I will likely have any free time to enjoy myself, or whether the next 3 years are going to be a long, hard battle with hardly enough time to pause for breath?

Homework Statement This is the equation y = y0e-kt Homework Equations b) Show using your expression for λ that if at time t1 the amount is y1, then at time t1 + λ it will be y1/2, no matter what t1 is. The Attempt at a Solution y1=y0ekt1 that part I got. Then the answer key...

From what I've read all processes of a thermodynamic system are irreversible because some energy will be lost to the surroundings but I don't understand why that can't be reversed by getting the surroundings to put that energy back into the system. Let's say I have a gas canister with a piston...

Wouldn't that suggest that life is a rare event in the universe? If it were common, shouldn't we expect it to have developed more than once on Earth?

Hey, not sure if this is the correct forum but it seems physics will ultimately bring down the telescope. Why can't we leave the Hubble in space until it doesn't work anymore? It doesn't have any space crew to kill, it would break up on re-entree harming no-one and would continue to inspire our...

Hi all, If we find some fossils there, will we be able to tell if it's DNA-based? Similarly if we find fossils (or even current life) on Europa what is it likely to be based on? I'm very curious if extraterrestrial life is like what we have here on Earth or not. It seems clear that...

I am currently trying to use calculus to solve a problem that I have been trying to determine for some time. I will present what I have determined so far. The Problem: A hero in a popular video game (In this case LoL) regenerates 7.5% of his attack damage as mana every time he damages a...

I don't know how to solve the questions that my lecturer gave me. I not understand about probability of half life. Can anyone explain to me and help me solve the questions as well? My lecturer ask us to prove the probability as shown in the picture.

Here are what I might call the ages of my life: Year 0-3: Unremembered. Years 3-10: Awakened. Years 10-13: Rebellious. Years 13-19: Sublime. Years 19-25: Disturbed. Years 25-35: Idyllic. Years 35-41: Panicked. Years 41-52: Romantic. (Notice the alternations.) And yours?

Even though life on Earth spans such diverse creatures from bacteria to humans, at its core, all life on Earth is pretty much the same. Life as we know it uses the same four bases to store information in DNA, the same 20 amino acids to build proteins, and the same genetic code to convert DNA...

Hi All, I'm a newbie here and I don't know enough about physics to answer my question, so I will submit what I think I know to be true, then pose some questions, therefore please pardon any allowable mistakes. 1) Time is immaterial for my purposes in this posting, at least in a...

Nickel-Iron batteries are making a comeback in the renewable-energy industry. My personal interest happens to be for wind generator/solar power energy storage and also for a pendulum gear-driven clock design that I am working on where I need a minute amount of stored power to operate a small...