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  2. Ghideon, I think your forgot the third measure, namely that there are 'two Ligo's', and a Virgo. If not all three measure the same effect at nearly the same time, it is something local.
  3. Today
  4. As LIGO is able to detect gravitational waves, some energy has to be taken from those waves. As electromagnetic radiation from some of the sources is comparatively extremely easy to detect, the energy absorbed by even the whole earth would be very small, with no detectable effect on the gravitational waves. Some of the comments after https://stuver.blogspot.com/2012/07/journey-of-gravitational-wave-i-gws.html look at different ways energy could be absorbed.
  5. Ibbb

    Dominant-Rezessive, alleles

    I am just interested in biology and genes how it works and the possibilities which genes my child would get. According to the punnet Ssquare, if the father has blue eyes (bb) and the mother has brown eyes, but is a carrier of blue (Bb) the child could get blue eyes. But how is it with if the father has bb and the mother have BB (brown eyes, and no blue allele)? ...according to the punnet square the child will have brown eyes, but I have seen children with blue eyes and blond hair despite the fact that the mother is not a carrier....just look at Shakira and her son, this is the same constellation..so the question is it is possible that the baby get blue eyes when it’s BB and bb ? Maybe genetics are a little bit more complicated than the punnet square..because of this I am here to ask in this forum. Thanks a lot
  6. Michael McMahon

    Suicide Prevention

    The experience of pain can encourage solidarity. Pain of course viscerally hurts. So I find it ridiculous any notion that some are "selfishly" dead or that the mentally ill are "arrogantly" in despair. As I've said before I'm not at all criticising society. I'm merely disagreeing with a few comments one sees around the web.
  7. IshaanM8

    Predicting Further Values in a Set of Data

    We don't have to use polynomials. There's multiple ways my teacher tells me, but because this is a "problem - solving task" we're to think up of something of our own. Thanks for the tips, I'll definitely check out Runge's Phenomena and ARIMA. Cheers! This is "Maths Methods" In Australia which is the 2nd hardest subject for "Mathematics" Currently Year 11 I'm using the polynomial of 6 because that's the highest available polynomial in excel. I've plotted them and they're all very similar to each other. I then got an average of all these data values and got an "Average Year". I'll be using the Equation from that "Average Year" graph as my Model. But is there anything else I can do to "Refine" it and make it even more accurate?
  8. I’m not sure. I guess it might be the small (tiny) amount of lensing ?
  9. Strange

    Oh no! Not another conjecture!

    Yes (as far as we know). Acceleration started relatively recently - about 5 billion years ago I believe. I’m not sure what you mean by “leave a vacuum” or why that would accelerate expansion. There was a vacuum there before and would be again afterwards And wouldn’t creating “more vacuum” (whatever that means) slow expansion? However, the non-zero energy of the vacuum that allows virtual particles to appear and disappear was an obvious candidate for “dark energy” to drive acceleration. The problem is that this energy is about 10120 times too large.
  10. From the source https://stuver.blogspot.com/p/informational-posts.html, bold by me: I'm curious, what are these negligible effects? Without knowing what explosions you might have in mind I'll answer regarding earth vibrations in general. As @Strange said, a lot of effort goes into making sure vibrations are not detected. LIGO uses two basic strategies to shield the detectors from Earthly vibrations, referred to as “Passive” and “Active” vibration isolation systems. Source and more info: https://www.ligo.caltech.edu/page/faq
  11. Michael McMahon

    Suicide Prevention

    Though rare, there has actually been suicide by burning. The poet Sylvia Plath died by putting her head into an oven. Self-immolation by Buddhist monks as political protest for instance has been documented. People who've made suicide attempts are sometimes left with disabilities. There have been cases of the terminally ill dying by suicide. To understand cowardice it may be best to first look to the opposite concept; bravery. I've frequently read that bravery is not the absence of fear but overcoming fear. So there is an element of fear in all death irrespective of how people respond to it. Personally I don't understand how WW1 analogies are helpful given the amount of controversy over the actual purpose of that war. Even knowing you are going to die doesn't always lessen the pain. In fact in the death penalty debate the uncertainty of inmates in death row is often cited as increasing the inmates' pain. Elderly death is obviously still very painful even though they've had up to 80 years to prepare for their death. We all have the same pain fibers so technically deliberate injury and accidental injury would both be highly painful. For people who make such an argument about relatives who find the body of a suicide victim your burning example perhaps wasn't good.
  12. John Cuthber

    Light

    Like circularly polarised light?
  13. Hrvoje1

    Quick LaTeX Tutorial

    [math]\sqrt{a}[/math]
  14. Mental Dynamist

    Mental Momentum (short essays about mind and brain)

    Here’s a full summary of my theory. I’m still organizing the supporting evidence. Please ask me if you have any questions. The Cortical Theory of Mental Dynamics The whole theory has four parts: Microscopic Mental Dynamics: The unit scale mental dynamics (time scale ~ a second to a minute). Key concepts: mental motion, intensified unit, interconnection, convergence, incorporation, time and spatial-integration, quasi-linearity. Mesoscopic Mental Dynamics: The unconstructional mental dynamics (time scale ~ minutes to hours). At this short time scale, assuming changes in our brain happen only at electrical (firings of neurons) and chemical (depleting and recharging of neurotransmitters) level, not at structural (growth & decease of neurons and connections) level. Deal with the transition of thoughts between fields, e.g. talking casually from topics to topics. Key concepts: concomitant habituation, potential, convergence control. Macroscopic Mental Dynamics: The constructional mental dynamics (time scale ~ a day to years). Neurologically, taking into account the structural evolutions in our brain. Behaviorally, analyzing the construction of a field, e.g. learning a new subject. Key concepts: connective construction, constructional potential, potential preservation, potential transformation, the three-stage construction. Constructional Grand Cycle: Linking mental dynamics from microscopic to macroscopic. Showing how we end up doing what we’ve learned through years (like doing math) inattentively as if out of our instinct. Key concepts: convergence selection, constructional collapse, pattern migration. Microscopic Mental Dynamics: (the initial part of this section has been discussed, please refer to the earlier summary) Thinking happens that the full activation of one unit (e.g. idea, concept) in our brain always activates part of other units. Through subsequent firing, activated units compete until only one unit remains and is fully triggered. So on and so forth to produce a linear mental motion perpetually moving forward in time. This triggering mechanism makes ideas/concepts in our brain 1) highly associable, and 2) distinguishable from its surroundings. A unit, as it incorporates more of other units, gains potential (i.e. becomes generally more likely to be triggered) and becomes more distinguishable from other units. I’ve also introduced time-integration and the equivalence of time - space (connectivity), showing we can make sense of the firing of individual neurons by analyzing the collective firing behavior of groups of neurons. In terms of measurement, I’d say we can either measure the temporal behavior of the firing of cortical neurons accurately, while the spatial measurement is integrated across space (e.g. EEG), or measure the spatial behavior accurately, while getting an integrated measurement across time (e.g. fMRI). Although on a larger time scale, our thinking appears linear, on a smaller time scale, it is quasi-linear – multidirectional because any single unit coactivates multiple other units at any given time. Mesoscopic Mental Dynamics: In our brain, the synapses (the connective nodes between neurons), while transiting firing signals, will deplete neurotransmitters, making it less able to transit firing signals. This leads to habituation, which pushes our thinking perpetually forward without retrograding to what’ve been thought about. Because of convergence – the overlap in meaning representation in our brain, the habituation of one thought will concomitantly habituated part of its closely related thoughts. This leads to the habituation at the field level in a much larger time scale. When solving a mathematical problem, for example, we can’t think out all the solutions we can potentially think of at once because after some solutions have been produced, habitation will accumulate so much that our thinking loses cohesion in that field. Our time of thinking can be regarded as a mental space for thoughts to occupy. Here I define mental potential – the ability of a certain thought (or a certain field of thoughts) to occupy our mental space. Mental potential is originated from the firing potential of individual neurons and the chemical potential of synapses – that each neuron has a certain likelihood of being triggered, and each synapse has the potential to transmit a certain amount of firing signals without recharging its neurotransmitter. Mental potential is manifested in two scales – the unit (idea, concepts, and etc.) scale and the field (subject, topic, and etc.) scale. At the unit scale, potential is the general likelihood for a unit to be triggered. At the field scale, potential is the duration of thinking within a field once thinking gets into it. While thinking within a field, habituation accumulates. But when we think meditatively (as opposed to being aided by sensation), our thoughts don’t jump across different fields. We stay in-field until the potential of that field expires. It happens as if we’ve created an inner mental environment to immerse us into that field. This inner environment is the firing in the prefrontal cortex. When thinking meditatively, the prefrontal cortex (frontal) and the posterior cortices (posterior) are like two people talking to each other – neither tends to say things that’s entirely foreign to the other person, because two systems (two people) always overlap, and the overlap always feeds back to the brain and strengthens that overlapped line of thought. Once we’ve been thinking in a field long enough, the two systems (frontal and posterior) gradually converge to the same page. The resonation becomes strong. And our thoughts seldom get far away from any of the two systems, thereby staying in-field. Thinking, in the mesoscopic scale, is alternating between the intensive in-field state and dispersive inter-field state. The later happens when thinking is transiting between different fields. This distinctive transition mechanism is resulted from frontal’s convergence control, which makes use of habituation to specify thinking direction. When solving a mathematical problem, for example, we first figure out ways that could possibly work and then try out one way after another. In this way, subfields are created within a given field, so that mental motion and habituation are concentrated within one subfield. It makes thinking definite instead of dispersive. It at the same time makes these unentered subfields less habituated, so that their potentials are preserved. It therefore makes the in-field thinking more sustained and more fruitful. When solving problems, the potential is the total space of a paper, and convergence control produces our plan to draw out more stuff on that same piece of paper. The ability of convergence control develops with age and varies among individuals. This developmental trajectory can be clearly seen 1) behaviorally: children tend to solve problem in a poorly planned way, tend to speak individual words rather than well-structured sentences, tend to be easily diverted, tend to produce jumpy thoughts, can focus on doing a thing for a significantly lesser time; and 2) neurologically, children’s prefrontal cortex is developed much later than the posterior cortices. Macroscopic Mental Dynamics: Thinking is constructional, changing the ground upon with it happens, thereby making later thinking different. Thinking is also associating, linking together previously far-away thoughts. Constructional potential is the open space for construction. It is also the connection that could be made between distant thoughts (i.e. the connective constructional potential). Learning new knowledge is connective construction. And the potential for us to learn new things is determined by our constructional potential. Constructional potential has two aspects – potential preservation and potential transformation. When reading a thousand-page textbook about neuroscience, for example, generally, on the next day you tend to have the same potential (i.e. tend to spend the same amount of time) to read the book as on the previous day. This is potential preservation – that the potential of a field is preserved. But on the next day, you don’t have the same potential for the stuff you’ve previously read. The things you’ve previously read transforms into the potential for you to read new related material. This is potential transformation. The construction of a new field happens in three stages – 1) familiarizing, 2) intensive, and 3) habituated. In the first stage, the potential of the new field is transformed from the potential of other fields. Therefore, how easy it is to learn a new subject, which is usually hardest at the beginning, is determined by how much potential could be transformed into the new subject. At the second stage, the in-field potential is generally preserved. This is a stage of pure love – the love for the field itself. In this stage, thoughts in the field will strongly occupy your free time of thinking (e.g. ruminating the storyline of the novel you’re reading at the break of working hours). Finally, we get to the third stage where potential is generally transforming from in-field to other fields. There, you’ll find that you need a holiday to do something else. Constructional Grand Cycle: The neurons in our inner system – frontal – compete in firing frequency. The ones that receive more firing signals are preserved, and the ones that get less firing signals are selectively discarded. This is called convergence selection: the frontal neurons first selectively connect to the posterior neurons (neurons in the posterior cortices) that incorporate most meanings and are therefore fire most often, and then actively control these posterior convergence neurons to make them fire even more persistently (manifested as thinking staying in-field). Convergence selection creates a sequence of action – a pattern that resonates between frontal and posterior. While the pattern is activated over and over again, the connective intensified, and the sequence of action collapses into an intensified unit. As the result of this constructional collapse, the pattern reduces in firing duration and potential, and in the number of frontal neurons to control it. In the end, an action that we used to take a long time to perform with our full awareness collapses into something so transient that we could perform inattentively. While constructional collapse happens, the frontal firing pattern is preserved and migrates to other parts of the posterior. As pattern migrates, we apply the pattern (could be theory, method and etc.) we’ve developed or learned onto new problems/situations. If the pattern is still applicable, it will result in a resonation between frontal and posterior, a constructional collapse, and a further pattern migration. If not, a new round of convergence selection will be initiated to generate a new optimized pattern.
  15. pzkpfw

    Light

    Polarising filters may be relevant.
  16. Ian Martin

    Light

    Like a spring
  17. Hi. Need help with Defining energy audit for pumps . Help please.
  18. Bufofrog

    Oh no! Not another conjecture!

    If the virtual particles appear and immediately disappear, then nothing is added.
  19. I don't agree with part or all of this but I suppose I can see its relevance for the following post. I tried to indicate I was only concerned with initial and final conditions in my example of how an isolated system can increase its entropy from one well defined value to another well defined value. The total work done in getting from the low entropy state to the final high entropy state, which is an "equilibrium state" where the entire volume y (or A plus B) is in equilibrium, is zero. While transitioning between states work is done. Also the temperature of the gas is lowered and it acquires kinetic energy. As the volume y comes to equilibrium all this work is transformed to heat. At equilibrium the temperature of the gas in the volume y is the same as it was in x.
  20. Yesterday
  21. QuantumT

    Oh no! Not another conjecture!

    Thanks for not shutting me down. Yes you are right. I knew where to put it, but I got carried away and hit submit prematurely, because I was confident about the details in it. Regarding evidence, I was hoping the in-house mathematicians could clarify or dismiss it. If not, it seems logic that anything added to a volume adds to it, even if it's a vacuum. Quantum fluctuation is the main culprit behind the big bang singularity after all, so it would only seem logic that fluctuation could also accelerate the cosmos.
  22. Phi for All

    Suicide Prevention

    Then why don't more suicides burn themselves? I'm just saying it's a poor argument, that the pain is the same. I disagree with your third paragraph.
  23. swansont

    Oh no! Not another conjecture!

    ! Moderator Note At almost 300 posts in, you should know where “I have a conjecture” should go, and that we need a model and/or evidence - some way to test it. Most of the universe is already a vacuum.
  24. QuantumT

    Oh no! Not another conjecture!

    Is the universe still accelerating? Sometimes I read articles that argue against it, so I'm not totally sure anymore! But if it is, I have a conjecture that might explain it. It is based on quantum fluctuation. (1) I might not be the first to think of it, and (2) it might be mathematical impossible, but here goes: Quantum fluctuation is (as far as I know) considered a come-and-go phenomena. Hello, goodbye. 2 - 2 = 0. But what if it leaves a vacuum? A tiny tiny vacuum? If so, there must be gazillions of tiny vacuums made every second. Speeding up the cosmos? (Sorry if this is wrongly placed! Feel free to move it to Speculation if needed.)
  25. Michael McMahon

    Suicide Prevention

    It's not so much about who was in the most pain but that there is pain in all death.
  26. Phi for All

    Suicide Prevention

    Probably why I specifically made sure to say: You claimed calling suicide cowardly wasn't right because both the suicide and the accidental death have the same kind of pain. I don't think that's true in most cases. Suicides get to choose how and where, they know it's coming, there are many factors that make it less painful. I just didn't agree with that part of your argument.
  27. Michael McMahon

    Suicide Prevention

    Well I think there's a difference in tone between reassurance and ridicule. I agree that we should by all means try to reason the person out of it and strongly encourage them to live; to remind them that the pain is temporary and it will eventually go away. But if a patient just cannot deal with the immense stress and pain they're under I wouldn't try to physically stop them killing themselves. I'm didn't say suicide prevention itself is being turned into taunting but just some opinions you read about online. People suffering from schizophrenia, for example, may have delusions. Pointing out the errors of their logic is certainly helpful. But I don't think "ridiculing" the person will solve it. It could easily backfire and make the person more guarded and defensive and less likely to seek help. Mental illnesses can be quite different. There are bullying victims who may contemplate suicide; chronic back pain sufferers, depressed individuals and so on. Each may require a different strategy in order to help them and prevent suicide. I'm not sure what you mean by your dying examples. I'm afraid there are many different methods of suicide.
  28. CODATA recommended values of the fundamental physical constants: 2014* - https://ws680.nist.gov/publication/get_pdf.cfm?pub_id=920687 ---- The kilogram, symbol kg, is the SI unit of mass. It is defined by taking the fixed numerical value of the Planck constant h to be 6.626 070 15 x 10–34 when expressed in the unit J s, which is equal to kg m2 s–1, where the metre and the second are defined in terms of c and Cs. This definition implies the exact relation h = 6.626 070 15 x 10–34 kg m2 s–1. Inverting this relation gives an exact expression for the kilogram in terms of the three defining constants h, Cs and c: which is equal to The effect of this definition is to define the unit kg m2 s–1 (the unit of both the physical quantities action and angular momentum). Together with the definitions of the second and the metre this leads to a definition of the unit of mass expressed in terms of the Planck constant h. https://www.bipm.org/en/measurement-units/
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