Years Definition and 595 Threads

...the universe look like? About the same as now? Rusty

I am currently a physics undergrad at a state school with a decent physics program (as far as I know). This is my third year as a college student, but I am only in the second year of the physics undergraduate curriculum here. If I continue at the current pace, I will graduate a year late, with...

Hello readers, I have been thinking and if you bear with me hopefully I don’t sound too mad!. I have read an interesting article and in it a leading scientist has claimed that A detailed, functional artificial human brain can be built within the next 10 years. Henry Markram, director of the...

okay. i understand that stars can 46 million light years away despite the universe only being 13.5 billion years old. The universe is expanding. However what i dont' understand is how can we see a star that is say 20 billion lights years away if it takes 20 billion light years for the light to...

In Maine in 1909 the Fernald Law was enacted that required hydroelectric power to be sold in-state only. My understanding is that damming rivers was considered a "taking" that hindered some interests (including the driving of whole logs), so the hydro-power had to be sold in-state to provide...

Hi, I am trying to understand the general status of Lambda-CDM model of cosmology and specifically how it is thought to explain the expansion of the universe for the first 7 billion years. Rather than replicate too many equations, this http://en.wikipedia.org/wiki/Friedmann_equations" outlines...

this a creationist question. i am not a creationist but a creationist friend asked me this question. didn't have the answer. the moon is moving away from us at a rate. billions of years ago at that same rate the moon would have been "touching us"? don't know the answer.. was the moon always...

Suppose you wanted to reach Alpha Centauri in 100 years. a. How fast would you have to go, in km/hr3 b. How many times faster is the speed you found in (a) than the speeds ofour fastest current spacecraft (around 50,000 km/hr)?

Is it possible in any USA universities to complete a bachelor degree in only 2 years by passing all the examinations required for graduation with attending laboratory classes only for some one who have actually Self studied physics before and is very good in it?

Hi all, it's my first post here, and I'm glad to have found it. I'm a software engineer by trade, but I've always been immensely fascinated by cosmology, and I think it's my true passion (when I went to school, I was concerned that pursuing cosmology would not pay the bills, so the pragmatist in...

So I received an email today about how Mars is supposed to be the closest to Earth in like 5000 years and that it should look like a smaller moon directly next to the normal moon. I looked around the internet and some sites say that its a hoax. Does anyone know anything about this at all?

Homework Statement The solar system is situated 26,000 light years from the centre of our galaxy, the Milky Way, and it orbits the centre at a speed of 220 km/sec. Calculate the time required in millions of years for one orbit. (NOTE: The circumference of a circle = 2 pi r where r is...

Homework Statement 5.10. Definition. A permutation of a finite set S is a bijection from S to itself. The word form of a permutation of [n] is the list obtained by writing the image of i in position i. We write n!, read as "n factorial", to mean n*(n-1)*(n-2)* ... *2*1. Homework...

I "stumbledupon" this article this morning. A battery that used radioisotopes and is powered by the decay of the radioactive material. Sounds like it would work. Is this legit? If so it seems like a pretty serious innovation. I'm sure this battery if developed for the public would have a...

How many people graduate from their undergrad in less than 4 years, but also have been able to get into top programs? I really want to know. Like I know a lot of people take a load of college courses in high school and pretty much have the ability to graduate in less than 4 years. Are...

Hey So, I did my physics degree a while ago, and I've been missing the head hurting that theoretical physics used to cause me; I'm guess I a bit of a masochist :P As I only did special relativity at uni, I've decided to learn the general variety. Can anyone recommend any textbooks on...

[Delete] Grad school/career change after 5 years of working. Sanity check. Edit: I guess I was just trying to convince myself, and I think I'm convinced. Will probably post specific questions later.

Okay, what I really want to ask is how often do people graduate in less than 4 years from a 4-year bachelor program and they actually get into top programs? Will grad schools be impressed that you graduated in less than 4 years or look down on you because you may not have enough experience?

What's the likelihood of light striking some interstellar gas and being absorbed, then re-emitted, and the re-emitted light actually being the light we see rather than the original light from the source? Also, what about the likelihood of reemission after passing through the heliosphere...

roughly 20-40 degrees! Thats seems like a fairly large increase to me. The reason was to benefit and better utilize fuel injection systems, however, the steel is now potentially at weaker temperatures. What would most likely be the ideal operating temperature for engine blocks such as, steel...

I'm majoring in Physics and Astronomy, and I am going to be a sophomore next year. My problem is that there are so many cool classes that I want to take that 4 years won't be enough time to complete them all; this is true even though I went into college with 30 credits from my credit-by-exam...

How many years does it take for one to acquire a doctorate degree in engineering?

Hey guys, I have heard that taking five years to graduate is frowned upon by grad schools. Is this true, and if so, to what extent? Let me take a minute to explain my situation. I'm a rising junior, and I only decided to become a science major a year ago. I'm a neuroscience major (but you...

I am going to get 4.0 on each semester to save my gpa.

I watched on PBS a documentary about 'Richard Proenneke' last year. His story struck me and for days made me think what life would be like in isolation, away from civilized world? It's an interesting story to learn about for those who haven't heard about him...

Hello all. Not sure how many of you remember me ... :) Its been a long time - 6 years or so. Have been busy - moved 2 jobs and am in a fairly senior management position now. Had a son 3 years back. Sobered down considerably (no more aggressive arguments from me) ;) So who's still there...

(http://en.wikipedia.org/wiki/Observable_universe) If the universe is 13.7 billion years old, how is the diameter 93 billion light years? Light travels 1 light year for every year. Then if two particles were expanding outwards to form the size of the diameter, it would be...

I just complete year 1. I am a math major and i am attending a 3-year curriculum university. I want to learn sth more concrete than math so i wish i can major in physics. Can i finish physics degree in 2 years? 1.In my estimate, i can take all the core courses but will they be enough if i want...

Hi everyone, I have been on this forum since December last year. I have read many interesting threads by twofish-quants and many other members about the possibility of working in Wall Street after obtaining a Physics PhD. Although I understand that a career in Wall Street is really financial...

PBS NOVA special: Mount St. Helens, back from the dead http://www.pbs.org/wgbh/nova/sthelens/ Mount St. Helens - 1980 https://www.youtube.com/watch?v=bgRnVhbfIKQ https://www.youtube.com/watch?v=njV9ski1gB4 https://www.youtube.com/watch?v=z1gpnu-fdUU...

So I got to thinking...it might be better for me to delay graduation by a year..or maybe just a semester. But I need advice on this issue (and others) from a lot of different people, and I figured this is one of the places I should ask. I just finished sophomore year and I feel like I'm not...

Best regards to all of you, I am 30 and some years old.I finished general high school-gymnasium in my country about 15 years ago.I used to love physics at ordinary and high school time.I competed in physics with decent results.When I was 19 I were in the wrong direction(enrolling in some...

http://news.yahoo.com/s/ap/20100508/ap_on_hi_te/us_tec_fragile_internet" By PETER SVENSSON, AP Technology Writer Peter Svensson, Ap Technology Writer – Sat May 8, 10:33 am ET and Like the huge oil spill recently with its terrible consequences, not until someone by accident or...

oops thread here: https://www.physicsforums.com/showthread.php?t=400913

[PLAIN]http://i.i.com.com/cnwk.1d/i/tim//2010/04/19/fgsdg_370x278.jpg http://www.cbsnews.com/8301-504083_162-20002789-504083.html Not the result of Islamic extremism, this was the result of homegrown discontent run amok. How many hate-radio jocks, disreputable news sources, and nuts, are...

I graduated from a top 10 liberal arts school in 2007 with a degree in math. After school, I worked for a year and change as a computer programmer and I'm now employed as an actuary. Getting an advanced degree is an idea I've entertained for a while, and now I want to try and achieve that...

Homework Statement Hi! I'm stuck on this one too. "A rock contains the radioactive isotope Rb-87. A piece of this rock contained 2,05*10^20 Rb-87 atoms and 8,25*10^20 decay products per kg. The half-life of Rb-87 is 47*10^9 years. How old is the rock?" Homework Equations...

Edit:Damnit, forgot to finish the title. Sorry! "Nervous about scheduling courses for next two years" I met with my faculty mentor today and I'd like some quick advice about classes for next semester. I'm a semester behind in physics (but all my general education requirements are done, just...

Relativity(Light years)? PLEASE HELP! Homework Statement Imagine an astronaut on a trip to Siris, which is 8 light years from Earth. On arrival at Siris, the astronaut finds that the trip lasted 6 years. If the trip was made at a constant speed of .8c, how can the 8 light year distance be...

Here's my situation: I'm a math student in their second term of their junior year. I didn't do so good in my first 2 years of college, and even failed a couple of classes (I did manage some good grades here and there though). This was mostly due to a poor work ethic and perhaps some other things...

in terms of continants, life, etc thanks in advance

much difference?

We continue reaching further and further back in time by observing galaxies that were born during the early part of the universe's existence. Some of the furthest galaxies we can see are 10 billion light years away, that is, their light has taken that long to reach us. In light of the Big...

Hi, Does anyone know of any recently published books that might bring the discussions in "300 Years of Gravitation" up to date? Thanks Lou

Homework Statement A super nova releases 1.9E45 J of energy over a 10 day period. It is 1560 ly from earth. A detector, facing the star, is a disk of radius 7cm. How much energy reaches the detector? (The detector is in orbit, so it can face the star for the entire 10-day period) Homework...

Hi, I want to resume my study of mathematics after a period of 9 years. SO i need your help and guidance. I have done a bachelors with specialization in Mathematics and later on I went to study Masters in Computers. So I am quite a out of touch with maths. So can u please anyone suggest from...

How do I calculate the strength of gravity between two objects say that 2 years ago were 2 light years apart, during which they became 0.5 light years closer, if during those two light years, the stars lost 50% mass due to fusion and light, based on their mass "now", or based on how much...

Homework Statement You wish to travel to the Pleiades (at a distance of 130 pc) in 10 years, according to the clock that you carry. How fast do you have to travel to accomplish this (express the velocity as a fraction of speed of light, v/c)? Homework Equations \Delta T...

Why do we take the "no. of years to compound the interest" as power? Suppose interest is given at 12% annually, compounded once a year. At the end of the year we will have (A = starting amount): A( 1 + 0.12 ) But if it is compounded twice a year, then at the end of the year we will have...

Ok, someone was kind enough to point out to me recently the obvious fact that the universe must be much larger than what we can see. Suddenly I feel like I'm literally trying to fit all of it into my head! I've always had this nagging feeling about inflation, but it's never come up to the...