Evolution Definition and 706 Threads

Hope you enjoy the following, http://www.youtube.com/watch?v=_Ssc1GsqHds&feature=player_embedded From, http://planetsave.com/2012/10/20/galaxies-trend-towards-more-ordered-disk-like-forms-over-time-upending-old-assumptions/

He calls evolution a lie from the "pit of hell", not to mention embryology and the Big Bang theory. http://www.huffingtonpost.com/huff-wires/20121006/us-congressman-creationism/

Here's a question, though I'm not sure if it is suited to the biology section, since it might overlap physics and Earth science. Hell, i don't know; I'm an English major :smile: Forgive me if i make any foolish assumptions. To what extent has the Earth's mass affected the types of life that...

I haven't read the Nature article. However, the newspaper article had a sufficiently complete description to infer what they did to infer. The scientist kept frozen samples of the distant ancestors, i.e., the bacteria that were first placed in a flask. Samples were taken from the flask...

Could someone explain SELEX (systematic evolution of ligands by exponential enrichment) or at least direct me to a good resource online because so far I have'nt found a decent explanation or website regarding SELEX online.

Homework Statement "Show that if the Hamiltonian depends on time and [H(t_1),H(t_2)]=0, the time development operator is given by U(t)=\mathrm{exp}\left[-\frac{i}{\hbar}\int_0^t H(t')dt'\right]." Homework Equations i\hbar\frac{d}{dt}U=HU U(dt)=I-\frac{i}{\hbar}H(t)dt The Attempt at a...

Please explain something I don't understand about the evolution of animals that have sexual reproduction. I thought that being a separate species means an animal will have sexual intercourse resulting in fertile offspring only if the partner is of the same species. I shall cite the giraffe...

We know the exact age of Universe and the earth. We know when life began on earth. Is the formation of life a result of random grouping of atoms and molecules? Is evolution the outcome of random mutations? If so, is the chances of such series of random mutations resulting in formation of...

I am aware that physicists are trying to derive born rule from unitary evolution. Has there been any success? What is the current status of that program?

Muahahahaaa, have a look they have found a perfectly preserved hominid skeleton inside the gaping mouth of a dinosaur: http://www.nmsr.org/Archive.html I like the length they went to to make up a true-looking story. Love the perfectly clean black dinosaur skeleton, ha ha.

A few day's ago, the great state of Missouri passed Amendment 2 which has a clause that specifically states http://www.sos.mo.gov/elections/2012ballot/fulltext_1.pdf Along with other religiously inspired text that was mostly already covered under existing law.

Dirac's "Quantum Mechanics" - the definition of the time evolution operator I'm reading Dirac's "Principles Of Quantum Mechanics" to learn more about the formal side of the subject. I have a question about the way he defines the time evolution operator in the book. Either there's a mistake or...

Hi, My understanding that one of the postulates of quantum mechanics is that the vector describing the quantum mechanical state of a system evolves in a linear fashion. My question is how this can be reconciled with systems where the system evolves in a non-linear fashion for example systems...

Hi, I several times heard that one way to describe the collapse of the wave-function is to add non linearities in the Schrodinger equation (I know that this approaches are not convincing but that's not my point), however, I don't see why a non linear SE would imply loss of unitarity? As long...

Why do we consider evolution of a wave function and why is the evolution parameter taken as time, in QM. Look at a simple wave function $\psi(x,t) = e^{kx - \omega t}$. $x$ is a point in configuration space and $t$ is the evolution parameter. They both look the same in the equation, then why...

Has anyone ever tried to establish an approx rate that languages evolve, in a similar way that genetic change was used to establish a molecular clock of sorts? (disclaimer: i know zero about linguistics) thanks someone.

Hello Colleagues, I am curious about a problem in Quantum Mechanics that incorporates the evolution of a Gaussian Wave Packet under the Gravitational Potential. What I am interested in is equation (3) in the following paper: "On the quantum analogue of Galileo's leaning tower...

Are Earthian biological systems, in their present state, more complex than they were 200 million years ago? Do evolutionary adaptations reach a limit in terms of they're effectiveness? Perhaps I can restate this question. If a species from 200 million years ago was transported to present...

When does helium fusion occur in an evolution of star? Well, i just need help in this confusing part of a star's life. First of all, when the sun finishes the H-fuel at core, why doesn't it immediatly use the H-fuel on the surface.. And then another doubt is, what causes the expansion of the...

Well, this topic is driving me crazy so any answers or replies should preferably be detailed and in an easy way.. My question is i want a sum up of the evolution of a low mass star... I will give my answer and tell me where are the dropouts.. Let me begin,With a protostar accreting hydrogen in...

Hi, I read the following recently in a book on genetics: The modular construction of genomes has allowed the relatively rapid evolution of biological complexity. I could'nt understand what the modular construction of genomes mean. Is it referring to genes which make up a genome?

In my book, it is written that in an evolution of a star, specifically the sun, IT will run low on hydrogen fuel but will have produced so much energy that it will expand slightly... Once H- fuel is used, the star will start fusing helium nuclei. This complex process can cause an explosion that...

I have seen discussions of universes with different numbers of spatial dimensions, universes without a strong arrow of time, universes with differing physical constants, etc. but I was wondering (here it comes, you are wondering) (LOL) would our universe be substantially similar with a...

Homework Statement The hamiltonian for a given interaction is H=-\frac{\hbar \omega}{2} \hat{\sigma_y} where \sigma_y = \left( \begin{array}{cc} 0 & i \\ -i & 0 \end{array} \right) the pauli Y matrix Homework EquationsThe Attempt at a Solution So from the time dependant schrodinger...

Is evolution(biological) feasible thermodynamically? Why and why not?

If you have some Hamiltonian represented by a 2x2 matrix ## H = \left( \begin{array}{cc} 0 & \Delta \\ \Delta & 0 \end{array} \right) ## And you want to use the time evolution operator ## U = \exp ( - \frac{i}{\hbar} H t ) ## it says that ## U = \exp (- \frac{i \Delta}{\hbar} t) ## Why...

At what point does perception enter the process of evolution. Are all the mechanisms of evolution 'blind'? In other words, it seems that a tremendous power is ignored - an organism can perceive their environment so why doesn't evolution capitalize on this instead of relying on random mutations...

Hi there, I know in this article - http://arxiv.org/ftp/arxiv/papers/1203/1203.4834.pdf - the authors discard the clicks at H at output b" with V at output c" (and vice versa), saying they are seperable states regardless of whether the decision to perform a bell-state measurement on photons #2...

Let's assume the theory of evolution was determined by scientists to be false and all of us accepted the idea that some supernatural being directly has created and continues to create species, with the exception of artificial selection. (This idea is a form of...

Does Evolution has a role on beauty of "Wood Duck" bird? Hey there, Lately I had a debate with a person on internet on whether beauty of Wood Duck has any relation to Evolution or not. At first he claimed that Evolution has nothing to do with beauty of species, and only narrow-minded...

Evolution is the passing of genetic traits from species to their offspring and the natural selection of evolution occurs because certain species die out when they are unable to cope with their environment and the surviving species continue to pass on their genetic traits, which serves as...

Homework Statement Suppose that a particular x-polarized cavity mode is described, at time t = 0, by the state |ψ(0)> = (1/√2)(|n> + |n+1>) Find |ψ(t)> for t > 0. This is best done in the Schrodinger picture. Evaluate the expectation of the electric field operator Ex and the uncertainty...

Hey, I recently watched a video on YouTube by Kenneth Miller, The collapse of Intelligent Design. One of the things he brought up in the lecture was a comparison between. Human and chimpanzee genome. What was specifically said was that we had 23 pairs of chromosomes while the chimp and all...

This is a doubt straight from Peskin, eq 2.43 ∅(x,t) = eiHt∅(x)e-iHt. This had been derived in Quantum Mechanics. How does this hold in the QFT framework? We don't have the simple Eψ=Hψ structure so this shouldn't directly hold. I'm sorry if this is too trivial

Homework Statement Hi, i would to resolve this problem of quantum mechanics. I have hamiltonian operator of a unidimensional system: \hat{H}={\hat{p}^2 \over 2 m}-F\hat{x} where m and F are costant; the state is described by the function wave at t=0 \psi (x, t=0)=A e ^{-x^2-x} where A is...

My question is the following: when in quantum mechanics one introduces symmetry, says that a states and observables transform both, in order to mantain mean values intact (kind of like a change of coordinate system), i.e.: |\psi>\rightarrow U|\psi> and O\rightarrow UOU^\dagger...

As I understand it, where a system’s Hamiltonian is not time-dependent, the wave function of a system that is in state psi(0) at time t=0 evolves as: psi(t) = sum, over all eigenvalues E of operator H, of exp(-i*E*t / hbar) * <E|psi(0)> * | E> If the eigenvalues are continuous it is an...

Hi, All: Please forgive my ignorance of much (most ) of this topic--and biology in general. Basically, I'm puzzled as to why most people do not find the taste of vegetables naturally attractive, despite vegetables being benefitial, maybe even necessary for a healthy life. It...

When I was very young, North Long Beach, Ca., was a very nice, very clean, very safe, very calm, completely white, middle-class suburb of Los Angeles. In the late 1960s and early ‘70s it began to deteriorate as slums in SW Los Angeles expanded and neighboring communities turned into slums. Then...

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 give me 3-10 points why you believe in the theory of evolution and/or the big bang? this is independant of any other theories. I'd like it numbered. and just brief points, like a topic and brief explanation of why this makes you believe evolution and/or the big bang to be true. I'll...

Can anyone explain how the time evolution operator commutes with the Hamiltonian of a system ( given that the the Hamiltonian does not depend explicitly on t ) ?

I'm womdering if real quantum randomness is important for evolution to work. In a universe without randomness i.e. where the future is predetermined, the amount of information contained inside the universe would be constant. No matter how old it is, the information content of the universe would...

Homework Statement With the time evolution time operator, where there is time dependent hamiltonian, show the new form of the feynman propagator between two states. Consider the Weyl Integral. 2. Equations from \newcommand{\mean}[1]{{<\!\!{#1}\!\!>}}...

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The theory is evolution is well established and maybe considered by some the cornerstone of biology but where are the experiments which prove it . We have never seen bacteria that turn into something else also where is the evidence for the theory in the fossil record ? Also I can't understand...

Philosopher Olaf Stapledon wrote Starmaker and the First and Last Men; supposed to be the best of the best in science fiction or future history according to some authorities. The books cover a time span of a gazillion supereons in the evolution of life in the universe. Planets are born and...

I was reading articles regarding to the changing of human DNA and how our DNA seems to evolving a rapid rate. With this I wondered if the human DNA does evolve? and if so would DNA gain traits that we would now consider super human? Any info in this area would be appreciated.

Its well documented that people generally are overconfident of their abilities - a recent paper in Nature speculates how it became an adaptive trait: http://arxiv.org/ftp/arxiv/papers/0909/0909.4043.pdf

I am an amateur studying physics on my own accord purely to satisfy my own curiosity and new to the forum , so please be gentle if i am stating something blatantly obvious or that has been discussed already. I was not studying this topic but had discussions with someone about DNA and then...