Amateur Definition and 98 Threads

Hi Just a brief intro/bio. Aged 68.5yo but mentally still a (responsible) teenager - that may be an oxymoron.. Interests: Astronomy, Cosmology, Spectroscopy, solar dynamics and anything Physics and maths related. Beyond that, add any other form of science and for more fun, I design, build...

I have been an avid amateur cosmologist for 40-some-odd years. I was hooked reading "The Collapsing Universe" by Isaac Asimov. I've been diddling about with it ever since. I learned relativity by reading "Discovering Relativity for Yourself" by Sam Lilley. And I've been playing with it ever...

Loved Astronomy as a child but strictly personal amateur. My love has evolved to include Cosmology, Astrophysics, and Quantum Mechanics. Although I went up to and through first year of college basics Physics, Calculus, and two years of Chemistry, I have forgotten much of it.

My website [Link redacted by the Mentors] named after my love of 2 hobbies , building Amateur Rockets ( Estes Type )and Amateur Radio ( Radio Ham ), It's free to enter if you just ask . In my spare time I enjoy using and writing excel spreadsheets, mostly for my own use, but free for anyone...

I'm just starting out with amateur astronomy and decided to buy a 10x50 Celestron Up-close G2 binoculars. I believe that tomorrow is the planet parade (the aligning of 6 planets) and I'd like to catch a glimpse of it. In the bortle 7 location that I'm in, I could only see a handful of stars...

Hi amateur scholar here learning new things Thanks for having me

Hi, my username is one I use for most forums, but my actual name is Steve. The references to homework on this forum suggest a rather youthful membership which makes me a positively ancient being of 58, lol. But I have long had a fascination with science in general and cosmology in particular...

"Associate professor Håkon Reiersen with the museum said the gold pendants—flat, thin, single-sided gold medals called bracteates—date from around A.D. 500, the so-called Migration Period in Norway, which runs between 400 and about 550, when there were widespread migrations in Europe." Found by...

Hi, I'm a recently graduated software engineer. During my time at university I had initially planned to double major in both physics and computer science but eventually dropped physics since I didn't expect that I would pursue a PhD for monetary reasons. I really enjoyed physics during my time...

I have the impression (I've not actually researched the matter) that some online weather services publish data from weather stations set up by amateurs. Do any organizations incorporate such data in their weather prediction models? I'd think that using such data would involve a sophisticated...

When I was a child I used to have a microscope. I don't remember the maximum zoom it could do. Nowadays when I look up for amateur microscopes on the web, they seem to go up to either 1000x or 2000x. Do you think it's enough to get some fun by looking at bugs and cells of onions for example? The...

I am searching for anything on quantum fluctuations and virtual bosons for someone who is a serious but amateur physicist ie. I have completed undergrad physics/math and some graduate level math at university. I am having a hard time finding anything that isn't beyond pop science. Not really...

I'm getting confused by the perturbation theory aspect of problem 2.2 in this book. We have to show that the energy eigenvalues are given by $$E_n = \left(n + \frac{1}{2}\right) \hbar \omega + \frac{3\lambda}{4} \left(\frac{\hbar}{m\omega}\right)^2 (2n^2 + 2n + 1)$$ For the Hamiltonian...

Hello, I am reading the book QFT for the gifted amateur and I have a question concerning how to go from the wave function picture to the Green's function as defined by equations (16.13) and (16.18) at page 147. ## \phi(x,t_{x}) = \int dy G^{+}(x,t_{x},y,t_{y})\phi(y,t_{y}) ##...

I am an amateur scientist interested in all fields of science. What voltage potential is used to measure the EC of water to approximate TDS of filtered tap water?

Hi All, I am kind of new to this, please be patient. I appreciate your input I have a SQL Server DB, I am trying to create a remote front end to give graphical, or at least simple access to the DB (Client-Server, of course). I would appreciate some suggestions. This is my way of breaking...

Hi, Could you please help me understand the following example from page 76 of "QFT for the gifted amatur"? I can't see how the following integral becomes Thanks a lot

Hey guys, I'm a super amateur at physics, but I occasionally like to calculate random problems that pop into my head. Today I was thinking about pascal and hydraulics, and wondered if I could devise a (hypothetical) hydraulic system that would allow my weight to lift an elephant. I want to...

I work with max. 18 V, hobby. Don´t want to mess around with AC. Which integrated circuits to buy to learn/ experiment with: -comparator -opamp -voltage regulators -voltage stabilizers -optocopler -CMOS -TTL -A-D, D-A converters -microprocessors -temperature sensors -timer -quartz crystal I am...

I work with max. 18V DC current, amateur. I thought the max. thing you can do is to mess up your multimeter, but I saw some capacitors exploding pretty big even on 9V on Youtube. As an utter beginner and with no mentor I would like to know about what to avoid to be safe. I am using max: 18Vs...

Beginner here. Learning about electronics. I would like to play with a thyristor, triac, diode, transistor, diode bridge, etc. using 1,5-9V batteries, wires, multimeter. I am buying a breadboard too. What kind of these you recommend for that purpose? There is a wide variety on the shelves please...

I know that the trend in commercial radio is towards digital. Suppose we go to all digital radio. My question is specifically about amateur radio. Will it still be legally possible for HAMs to operate analog radio systems? Any indications at all from the FCC or similar bodies outside the USA on...

What knowledge based are needed in relativity theory, not general public science education level, but true and mathematically. I have calculus and linear algebra education in university, Chinese engineering degree, quite rigorous in math education. Can I actually pick up relativity theory myself...

In exercise 17.1 we are asked to show that the propagator: $$G^+_o(p,t_x,q,t_y)=\theta(t_x-t_y)<0|\hat{a}_p(t_x)\hat{a}^\dagger_q(t_y)|0>$$ is the same as $$\theta(t_x-t_y)e^{-i(E_pt_x-E_qt_y)}\delta^{(3)}(p-q)$$ so we can take the time dependence out of the creation and annihilation...

Hi, I'm looking for plausible fiction based content regarding environmental destruction. Sort of future UV wars or something. So here goes. Would appreciate any ideas or feedback on what I've come up with so far. Several dissidents build 12ft mirrored parabolic dishes which shine narrow focussed...

Hello everyone! My goal has always been to be a researcher in physics. I am graduated in Electrical Engineering. My idea was to perform a master's degree and then a PhD, both in physics, with the aim of becoming a researcher. However, at this time I need to work, but I always have the night off...

I learned about entropy is chemistry, can someone please explain how this term is used in physics? Thanks.

In chapter 11, Lancaster takes us through the 5 steps for canonical quantization of fields, and in example 11.3 he derives a mode expansion of the Hamiltonian which ends in this: $$E=\int d^3 p E_p (a _p^{\dagger} a_p + \frac{1}{2} \delta^{(3)}(0)) $$ Which I have no problem with, but then...

In chapter 9 "Quantum Mechanical Transformations", example 9.3, can anyone explain how $$\hat{p}$$ in the exponential converts itself to q? Apologies in advance if this is very basic, but thanks for looking. $$\hat{u}(a)|q>=e^{-i\hat{p}\cdot a} |q> $$...

Astrographs are fast (f/4 or less) telescopes with large image circles (say 60mm or more); there are optical design considerations that make the specific designs somewhat more complex than 'regular' telescopes- primarily the strict field flatness requirement. While a 35mm format sensor is...

Hello all, First of all thanks for taking the time to look at my post, and thanks ahead of time to those willing to answer my question. I've always loved Astronomy and have done quite a bit of self-study over the years. I have a pair of binoculars but want to get a telescope. I'll start by...

Good Afternoon everyone, Question: What are some effective ways to generate a high voltage (Multiple KV) using amateur equipment? I've dealt with high voltage before, so I'm aware of the safety issues. Anyway, here is what I've got thus far: If you go on ebay, and search for high voltage power...

I just graduated high school and have quite a bit of free time. Since a lot of Astronomy today is done via computers, I was wondering if I can analyze data and contribute to the field of Astronomy by sitting at home, somehow, if possible. I've searched around and gotten sites like this...

I have a few questions about AM, FM and PM. 1. If FM (or PM) radio modifies the frequency of the signal, how is the signal picked up without having to change the frequency constantly? 2. If PM modulates phase, which modulates frequency, what is the difference between PM and FM? 3. Why is AM...

Hi all! Where are some good places on the Internet where I can learn about physical cosmology? Specifically any good websites that are devoted to physical cosmology that you know about?

i think it is possible but its too complicated to write down in english so i think comunication faster than light is possible without anything acctualy moving faster than light. If you had a big stick between Earth and the sun and you push the stick towards the sun for 1 inch it will instantly...

Sup guys and gals! Just another seventeen year old physics amateur passing by. People call me a scrub, but one day I shall be the hokage/top Pokemon trainer or whatever is equivalent in the field of physics. (Datte Bayo!) Things I love: Eureka moments, success after persistence, understanding...

Normally I understand Wick theorem as used in particle physics, but I guess I have a problem with using it in condensed matter physics. Or at least, I have a problem with a use of Wick theorem in the book T. Lancaster, S.J. Blundell, Quantum Field Theory for the Gifted Amateur at page 381, Eq...

From my view point as an amateur enthusiast who has largely forgotten basic high school physics, mathematics, science, cosmology etc., as I find myself taking up a renewed interest in these topics, I'm astonished at how easy it is to wander into the mine-field speculative, crack pot theories...

Having not been set up with a station for quite a few years I am thinking of setting up an end fed antenna for HF. It seems the only way I will enjoy a little 'hamming' again is to start out simple and quick. Trying to avoid clutter in the middle of the yard. I have enough tower sections get...

excuse me if this is too basic question. why is it that black materials BOTH "absorb" and "radiate" more heat ( energy ) and white materials do it less. i mean is there a rule that any material absorbs and radiate heat in the same amount and can't absorb more (like black materials) and...

Book recommendations for becoming an "amateur physicist?" Hi all. Despite my lousy grades in physics in high school, it was always my secret love. Even when I was little I dreamed of being like those guys on TV explaining how the cosmos began. My first year of college I even came here to ask...

He revolutionized amateur astronomy. http://www.universetoday.com/108150/john-dobson-inventor-of-the-popular-dobsonian-telescope-dead-at-98/ http://www.skyandtelescope.com/news/John-Dobson-1915ndash2014-240456881.html

Hi everyone, I've been reading posts here occasionally, and have been impressed with the amount and quality of knowledge that is being shared. I've just registered, and as my first thread I thought I would post some questions / thoughts that have puzzled me for a long time, related to...

Hi ! I have a basic question : What should an amateur astronomer learn to better understand the sky he's watching ? I love watching my sky at night (Even though the quality of it is discusting, too much light pollution.) But I feel I lack knowledge because I'm watching space, but I don't...

I've been wanting to learn physics for a while, and bought an intro book and read through it. Now I want to move onto some higher level physics and am having some problem with the math. My book glosses over how to write out field point vectors, and I don't really understand it in various...

Is it possible to detect exoplanets with amateur telescopes? If so what size would be needed. I have seen some amateur protoplanetary disks pictures and would one be able to tell if an exoplanet existed in it as I carved out the material for planet formation? Is it possible for us with current...

Background: I'm in my senior year as an accounting undergrad and plan to stay in the program and the field until I can become financially independent, hopefully very early in my life. I don't have a passion for accounting anything like what I do for science, health, and medicine (of which I've...

Hi, I am kind of new to this forum and I am a sophmere in high school. So far my school has been interesting and I've recently been exposed to amateur astronomy. I've been at it for a year and half. In fact I've took it very seriously now. I kind of wanted it to be my career and I do have other...