Years Definition and 634 Threads

I'm sure this is probably a stupid question with an obvious answer.. But i can't come up with it.. So, the observable universe is ment to be 90 billion lightyears across, right? And it's 13.8 billion years old, right? And a lightyear is the distance it takes for light and fields and stuff to...

Hey guys so I'm enrolled to start a physics major this coming semester but have been out of school since 2009 (im 24 now) and haven't done much if any related math or physics study since. Had always been quite good at maths and physics in high school but worried that i will have forgotten a lot...

Supposing immigration is heavily restricted in the future will there be an increased demand for home-grown US STEM in the next 4-8 years? How will these new rules impact the job market for US citizens? What sectors do you think will experience the biggest surge in demand?

Hello everyone. I have alredy introduced myself(https://www.physicsforums.com/threads/lets-get-started.901297/#post-5674898). As I mentioned, now in school we are studying log's, but in my self-studying I have already read about Complexs number and how to work with them(simple math...

I'm writing a story that set in the second half of the next century, but i think my questions are about real science. Lets suppose that current trends continue for a while, until either fossils depleted, or become unviable to use them, so for a few decades i guess. Is there significant chance...

We hear so often of the great advances of medicine. Every day one reads of breakthroughs in research in the news. But then I never hear of it again. I'm not a doctor or biologist, but am wondering what are the important discoveries ***and which had practical applications*** of the last 20 years...

Super moon Monday 11/14/16 . Full moon's closest approach in 70 years.

I have a ton of things I want to do in my life before I'm young. The problem is that I won't be so young for long! Ideally, if I get my PhD in about 2 years I will be on track with the things I want to do. Has this been done before? Why exactly is the average time needed 4 years? Why that number?

Great article on the Nobel Committee and their failure to select women of science for the Nobel: http://scitation.aip.org/content/aip/magazine/physicstoday/news/10.1063/PT.5.8191

hi, I got inspiration from alien, Prometheus, and knight of Sidonia(Japanimation) in these SIFI contents, I ve seen artificial things that stand quite long time. when it comes to man made structure, material, or method, I wonder is there any chance to survive million year on earth? structure...

I'm not sure if this specific question has been already covered. If a person in his 60s who had been say, a painter all his life, decides to instead learn to play an instrument, what happens to the neural processes in his brain? Will the brain use brand-new neurons to create a brand new...

Hello, My title is a little too long. I have graduated two years ago in applied physics at a master level and did nothing since then. I am isolated and I feel a lack of motivation to apply for PhD offers (and never had any motivation to apply for any other kind of job offers) and I lack...

If reality requires an observer, and life on Earth is only 3.8 billion years old- yet the universe is 13.8 billion years old, who was the observer for the first 10 billion years?

Hi, everyone. This is my first post and I'm glad I found this forum because I have some problems that I can't get much feedback for. I graduated from college about 15 years ago with a BS degree in electrical/computer engineering. My gpa ranged somewhere from 2.8 to 3.0. Based on USNews, my...

I was in Italy for a machine design company, i was there for 6 months

If I writed a physics textbook at 18 that countain all physics equations laws texts and facts from grade 9 to the first year of undergrad (freshman) and I will put in the book from where and how was derived each equation . Will people buy my textbook as a 18 years old ? And can I find a publisher ?

Just wanted to get the people of PF's opinion on this. I think we can all agree that we live in a technologically exciting time, and you'd be hard pressed to find a field that won't be revolutionized in some way in the next couple of decades. I'm in particular interested in technologies in the...

Surely this is a huge, huge find, is it not?? A living ecology, isolated for over 5 million years? http://ecowatch.com/2016/05/24/movile-cave-romania/ Scientists Uncover Array of Strange Animals in Cave That Has Been Sealed Off for 5.5 Million Years

Homework Statement A 25 year old programme for building new houses began in Core Town in the year 1986 and finished in 2010. The number of houses built each year form an arithmetic sequence. Given that 238 houses were built in 2000 and 108 in 2010, find the number of houses built in 1986...

Hi all, I graduated from university with a BSc in Physics (3rd class) in 2000. I was having some issues with depression then in my university years but I managed to graduate with a B average in my basic degree. In 2005, I was warded in a psychiatric hospital and diagnosed with schizophrenia. I...

Hello, I'll try to keep this quick and to the point. Feel free to ask if you have any questions. I'm 24 years old now. I finished my physics B.S. last year. I studied in Utah and did research for my university for 8.50$ per hour. I've been living in poverty since I was 18 trying to become a...

I know how to do half life problems and I even have a half-life calculator on my website: http://www.1728.org/halflife.htm However, I cannot calculate half-life when problems are stated in this form: End Amt = Start Amt * e^-0.0391 * t (in years) Half-life =? I know calculus but I find it...

Hi everyone, I have read here several times that in Europe you only need 3 years for the PhD, but almost every person that I know has needed between 4-5 years for completion. This added to the 2 years for the master, gives an average of 6-7 years for the PhD, which is the average time in the...

The Milky Way now has 49 known satellite galaxies, and the new one is the fourth largest. Link: New Scientist

Question: Sirius is about 9.50 ly from Earth. To reach the star by spaceship in 15.5 y (ship time), how fast must you travel? Answer in terms of "c". 0.4843c and 0.6129c are incorrect Relevant Equations and Constants: Attempt at solution: Can anyone help out I really don't know what...

Hello everyone. I am a 14 year old student and am truly fascinated by chemistry. As I tried various software, they all had a very complicated UI (User Interface) and confused me a lot as a younger student. After searching a lot, I decided to make my own chemistry software. This is the final...

http://gizmodo.com/frozen-tardigrade-brought-back-to-life-after-30-years-1753152359 Sorry if this is the wrong place for this post am only posting to get a few good responses if possible :). Is there any way we could extract the properties in the gnome of the tardigrade and genetically...

what do you think the nobel prize need in physics for next years 2016-2017-2018

On Kepler B#, humanoids have survived every mass extinction as a species for millions of years. On Kepler Bb humanoids haven't been there as long. Only tens of years instead of millions. In my story about Kepler Bb I have Robin and Lisa in a stone age type civilization when they are young...

So, Basically the question is in the title. I'm just about to start My undergrad and For many reasons, I'm strongly considering getting an As in physics before transferring to a bachelors program. However, I really don't want to miss out on anything, or for my junior college roots to affect my...

Homework Statement Suppose you decide to travel to a star 65 light-years away at a speed that tells you the distance is only 25 light-years. How many years would it take you to make the trip? Homework Equations ∆t=∆t0/(√ (1−v2/c2 )) / ∆t0 = ∆t √(1−v2/c2) L=L0√ (1−v2/c2) The Attempt at a...

Greetings! Having finished my A-Levels, some unforeseen circumstances had forced me to take 2 gap years before starting my undergraduate studies in Physics, and I hope to make these 2 years count by doing something meaningful. The first thing that comes to mind is work experience/internship...

The tittle says it all really, how did Black Holes appear so early in the universe, why not stars? arXiv:1601.05473 [pdf, ps, other] The Early Growth of the First Black Holes Jarrett L. Johnson (LANL), Francesco Haardt (Universita dell'Insubria) Comments: 13 pages, 9 figures, invited review...

Hello everyone What do you think is the greatest discovery in physics in the last two years? I think Higgs boson is the greatest one, isn't it? It was discovered by peter Higgs and François Englert and they were awarded the Nobel Prize in Physics.

I know of infinites disadvantages of started a physics phd at my age. I tried, but do not take me by my age...Chile, sudamerica. I have a Msc physics an one publication about brane world. At Chile , in my opinion exist very discourse about non discrimination, but there is much discrimination...

Greetings! I read this article on line, where it states that Voyager 1 has an appointment with a star, AC +79 3888, which is 17.6 light years away, in 40,000 years. However, if voyager is traveling at 35,000 mph, that number seems off. Shouldn't it be 319,000 years to travel that distance? I'm...

I was discussing with a friend about speed of light and time traveling and I realized something bizarre. I could be wrong so please correct my mistakes. So let's assume we want to go to our alien neighbour whose planet is 100 light years away. When we travel there with near light-speed, we...

Hello guys, I have a small problem and I hope someone can help me. I have a bit of information I want to "engrave" into this planet till our sun melts it down in 4,5b years. It's not important if someone finds it, wouldn't be possible anyway, but I want it to be 'somewhere' on or in this...

Hello Physics Forums, I've screwed up since I graduated high school 9 years ago. I really haven't done much during those 9 years. I'm now 27 years old and I want to go to college to major in physics. I intend to apply for a community college and then transfer to a university. Is it possible to...

I was looking a Leonard Susskinds background, and I noticed he obtained his Phd in 3 years from Cornell. Is this unheard of in theoretical physics these day. Was he just that special?

In short, I finished my AA at one college and had been working on my Bachelors from my current college. However, due to family circumstances, I had to take a break this semester (and possibly next semester too). I now desperately need to find a decent paying job for financial stability. I'm...

Applying for graduate schools (Masters) in ECE. Mostly top 10s and top 20s. Cumulative GPA: 3.35 GPA for the last 3 years: 3.85 GRE: Q170 (98% percentile) , V167 (97% percentile) Nice research experience. I also got an award for an innovative product I designed on the side, an honors mention...

A useful and concise (36 pages) history of the development and use of GR by one of the established experts in the field is posted today on the physics ArXiv : 100 Years of General Relativity by George Ellis. Garth

I'm entering my 3rd year, for a bachelors degree in Physics. I messed up in the first year and now I'm trying to catch up. Can I get a place in a university for a doctorate or MA afterwards?? Even if my grades are really good in each subject/course? I'm getting worried! Thanks.

How many years does a postdoc have to spent active in researches before he can attain a full position as a professor and has his own laboratory? Not too long ago I found a PhD thesis of my current group leader, it was written in 2000 or so and now (after 14 years) he has become a prof and has...

Is it true Florida and California will sink into the ocean in hundreds of years? I've heard somewhere that Florida might sink in hundreds of years time and that California in hundreds of years time might either sink or break off into an island.

I transferred into my school's physics program with all my core curriculum done, so I only have to take physics and math courses to finish my degree at this point. The physics program at my school is pretty small so pretty much all courses are only offered in either the fall or spring, and there...

I know it has something to do with the rate of expansion, but why are large intergalactic distances measured in km/s rather than units of pure distance like mega parsecs? What is the conversion?

Urs Schreiber submitted a new PF Insights post It Was 20 Years Ago Today -- the M-theory Conjecture Continue reading the Original PF Insights Post.

Hi, I am currently in my 3rd and final year of B.Sc Physics. Soon I'll have to start applying for a Masters degree. Is it true that you need 4 years of bachelor degree to get admitted for Postgraduate via GRE exam? If so, is there any university outside India which will accept my 3 year course...