BenSCBSc
Members-
Posts
12 -
Joined
-
Last visited
Profile Information
-
Favorite Area of Science
Physics
Recent Profile Visitors
1507 profile views
BenSCBSc's Achievements
Quark (2/13)
2
Reputation
-
Data from a few different areas of physics seem to favour the multiverse theory. Where some sort of phase transition occurs in a localised 'space' of a larger 'universe' and rapidly blows it up creating our universe in alternate dimensions. So I'm imagining this larger universe to be an extremely dense origin of matter/energy to begin with...... Also black holes seem to be miniature reversals of the afore mentioned theory, so where does the mass/energy go at the singularity of a black hole? Theoretically there is nothing there, gravity has crushed the mass into nothingness, so where has that energy gone? The gravity remains warping the space-time around it but the matter simply isn't there. As yet I haven't studied GR so I don't know what the mathematical explanation is? But if a black hole can be infinite in mass and infinitely small, the matter/energy is perhaps squeezed into other dimensions? Obviously I'm theorising with little experience but it seems more plausible than simulations to me.
-
Time travel & wormholes are in the realm of special and general relativity? Not quantum mechanics, as for dimensions? Maybe string theory, M theory? Or just plain old geometry? It would appear that your argument was flawed from the outset as the last 100 yrs has seen a huge surge in knowledge with respect to quantum mechanics. It is key to every electronic device you can think of in modern society. It has aided all the other sciences from biology and the discovery of the structure of DNA to palaeontology and NMR spectroscopy and Imaging. Our modern way of life would be extremely different without the advances in qm that have been achieved, it seems quite apparent that you don't really know what quantum mechanics is responsible for.
-
Help with NMR spectroscopy please!
BenSCBSc replied to BenSCBSc's topic in Modern and Theoretical Physics
I'm getting there, slowly. It looks like I do need to know all this stuff but I understand spin-spin coupling now and the intensity ratios are Pascals triangle. (I feel quite clever having recognised the pattern ) Actually just being able to understand what is going on is no mean feat! Thanks again for your help. -
Help with NMR spectroscopy please!
BenSCBSc replied to BenSCBSc's topic in Modern and Theoretical Physics
Thank you very much, I'm very grateful. There is quite a lot to get into there, but I have a couple of questions, Do the protons that are double bonded not rotate, because they are double bonded? Where you were talking about J-coupling (sentence below Splitting Tree diagram) and using protons A, B & C are these represented the first diagram? I'm not sure I understand how the number of peaks is representing the number of environments? I mean I'm not sure how these environments are counted, what determines a different environment? How is A different from C, I know C is bonded to an Oxygen atom and thus has different neighbours but how does this alter whatever it is your counting? I'm guessing because it has no hydrogen neighbours but if I take A that has 2 H neighbours how does that result in 3 peaks or is that 4 peaks because the central peak is twice as high (so it's integral is informing us that two of the protons are in the same environment)? I still don't know why it's 4 though and where you get 3 different spin states? I have been given more material to work through so maybe J-coupling etc will come up. I've kind of bubbled my way through half of the year, performing experiments including using a robotic telescope to image clusters and investigate stellar evolution & Compton scattering and had nobody to discuss any of it with so it's very refreshing to be able to ask questions about things I'm not sure about. Many thanks. Hi again, I was just looking at my new material and found this for 2.2 dimethylpropane? propane indicates that the structure consists of a single chain of three carbon atoms: carbon–carbon–carbon, ‘2,2’ indicates that there are two substitutions on the middle (labelled 2) carbon atom, dimethyl indicates that both substituents are methyl groups, hydrogen atoms are attached to the ‘end carbon atoms’ to ensure that the fourfold valency of carbon is satisfied. Can you tell me what is meant by 'substitutions' please? I haven't come across this term before and the diagram for 2.2 dimethylpropane doesn't show a chain of 3 carbon atoms? It has 3 x H bonded to 4 x C and those are attached to a central carbon. So it's symmetrical in 2 dimensions, the carbon atoms form a cross, not a chain? -
Help with NMR spectroscopy please!
BenSCBSc replied to BenSCBSc's topic in Modern and Theoretical Physics
Wow more magnetic fields (anisotrophy), so any anisotrophic effects will inform you if the system is pi or not. Can you determine anything else about the compound from anisotrophic magnetic effects? It looks like there's an awful lot to learn here, I imagine it takes quite a bit of practice before you can look at the resonance lines of a variety of organic compounds and accurately describe their atomic structure. I have been provided with chemical drawings for different molecular compounds and I have to be able to determine what their peaks would look like, also I am supposed to be able to describe what the compounds look like based on their names. I'm studying physics, so chemistry notation etc is not my forte. Looking at the scope of the subject, I'm not sure we have been given enough time (about 3 weeks). Perhaps I've misunderstood though, perhaps my tutor was referring to chemists or other users of NMR and not me, when she said 'alkane, alkene, alkyne, alcohol, amide, nitro & carboxylic acid are important? Or is it quite possible that I should be understanding the atomic structure of these function groups? Thank you very much, you have been very helpful. Do you know of any papers, journal articles on basic NMR particularly to do with 1-iodopropane & 2-iodopropane or something similar. I have looked at a couple: Unfortunately they either seem to be very complicated, far too complex for what I am doing or I can't get access with my athens? -
Help with NMR spectroscopy please!
BenSCBSc replied to BenSCBSc's topic in Modern and Theoretical Physics
Many thanks, I also found that the integral of the resonance peak increases with the concentration or number of molecules and since I am using CHCl3 and CHBr3, it means my hydrogen atoms increase by the same value. So you would know exactly how many hydrogen atoms are in your molecule. Damn that's clever! Many thanks for the link, I haven't had chance to look yet but I'm sure I'll be equally amazed. -
Hi, I am actually running measurements at the moment using 400 MHz 1H NMR spectroscopy. The purpose of spinning the sample is to average the effect of inhomogeneities (unevenness, deviation from a uniform field) in the main magnetic field.
-
Hi everybody, I'm struggling to understand how 1H NMR works. I think it might be best to explain what I do know and maybe somebody can fill in the gaps for me and/or correct me? The external magnetic field aligns the magnetic moments (spin) so that they are parallel/antiparallel (in a low energy state) to the magnetic field. A radio frequency is pulsed (400 MHz in this case) and the nuclear magnetic spins flip (putting them in a high energy state). So with the pulse, the spins are put through a process of relaxation & realignment, whilst doing this the nuclei emit a weak radio wave KHz which I can measure, but how exactly does this describe the molecular structure of whatever sample I have in there? And where does the rest of the energy go? I put MHz in and get KHz out, due to the conservation of energy I've lost some somewhere? A brief description will suffice, I just need to get my head around what is going on? Or if somebody can provide a link that explains it? I've looked and I have got a little information but not what I want. I want to know how the radio radiation signal I'm recording describes the chemical compounds I'm supposed to be looking at? Many thanks to anybody that can help me. Cheers Ben
-
BenSCBSc started following Modern and Theoretical Physics
-
Quite and very well stated. I have had this argument before with a 'physicist', or so he claimed? I can kind of understand why people might want to dismiss quantum mechanics as being irrelevant. Having a classical understanding of the universe works on the macro scale for harmonic motion, velocity, mass etc and one can consider oneself educated on the natural world, but then somebody goes and throws quantum mechanics into the mix and you know nothing anymore, you've been relegated to the learners bench again. So instead of learning what is a hard and complex subject, it is easier to disclaim it as theoretical and purposeless. I think that if people that already understand Newtonian mechanics, took a look at qm they would be surprised that it isn't completely out of reach, it just takes a bit of hard work and some effort. In fact some of it is simpler than the classical stuff. At least everything is quantised and so is all just multiples of the same thing!
-
Is there an equation that proves that Energy is always Conserved?
BenSCBSc replied to Maximillian's topic in Physics
The conservation of energy shows up in the equations of what ever it is your equating. Energy manifests itself in different ways, heat, light, kinetic etc. Therefore there is no equation for generic energy, conserved or not. Hope this helps -
To continue the list 8.understanding the mechanics of the Sun and other stars 9.NMR, fMRI and other medical scanning equipment 10. Electron microscope 11. Telescopes (outside visible spectrum) 12. Just about every electronic device you can think of. 13. Water purification 14.cancer treatments I can go on and on but I think the point has been made.