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Proper sushi sandwhich.

For the OP this is just a primer to help understand the basics of QFT and how force is applied. Keep in mind this is a workup I did on this forum a few years back but it saves a lot of latex. You should be able to get the gist of how QFT differentiates from QM. One difference to recognize and I didn't cover is that the Schrodinger equation is first order while the Klien Gordon is second order. (This is a conflict of QFT to QM that requires a seperate fix). The repair comes into play when you factor in particle number density... Just in case your not familiar with time derivatives (the overdots) https://en.m.wikipedia.org/wiki/Time_derivative This paper is rather advance but it will give you a good idea of how the Langrangian is used to describe the standard model. https://www-d0.fnal.gov/results/publications_talks/thesis/nguyen/thesis.pdf It should give you a good idea of what you are up against...

The governor in my state is re-opening most things on Friday, but many of the local businesses I love and frequent have already responded and posted things on their various social pages that can be paraphrased as... "Uhh... yeah, we're really glad the government is so optimistic and that's all well and good, but we're most decidedly NOT re-opening until we see more reductions in cases for a few weeks in a row. Absent that, we're not willing to put our staff and customers at risk... Hope shouldn't be Plan A and for now we'll stick to limited online ordering and curbside pickup." Meanwhile, the POTUS wants to re-open schools for May before summer starts, too. So tired of being led by incompetent grifters.

Yeah she cooks outside in primitive conditions but cooked bugs don't carry bacteria... flies do...

What is n, and why don’t you know it if you have a proton and electron interacting electromagnetically? Being able to do straightforward tasks is a simple first cut for proposals of alternative models

Thought it was kind of funny, that she swatted away flies, while she was cooking... crickets ? Wouldn't want to get bugs in your bugs.

Perhaps it helps to highlight some of the basic ideas behind the models underlying many of the strategies currently in play. A simple, but frequently used one are SEIR models or their variations. These are simple differential equations calculating how the rate at which folks move from Susceptible to Exposed to Infected and finally to Recovery status. You can think it as a simple compartment model in which the population is part of either of these compartments. Values such as effective reproduction number (how many people an infected person infects), length for which a person is infectious, initial number of infectious people and so on then determine the movement of the population through these compartments. From there, one looks at the expected number of infected folks at any given time and often using age-adjusted models (as well as other info, if available) one can estimate how many folks at any given time might need hospitalization. As the capacities can vary significantly, especially in larger countries, usually more local modelling is conducted to understand the health impact of different infection rates. The major factor that measures such as social distancing and shutdowns are affecting are therefore the expected number of folks being infected in a given time frame (essentially by adjusting the effective reproduction number). This is pretty much an established effect by now, with different estimates for different measures (and areas). So basically the major strategies revolve around these measures, as well as increasing health care capacities, if possible. So one might allow the transmission to increase a little, provided that the health care facilities are free, but may want to shut down again, once they go up. Two critical things we need to know, but don't know yet is how efficient immunization is going to be (either via vaccine or via infection) as well as a how long potential immunity will last. There are models for that, which in the simplest case just has a flow back from Recovered populations back to Susceptible after a certain time.

Several valid points regarding Sweden have been made in posts above. My experiences so far: -There is not enough data available to state anything conclusive regarding the current approach here in Sweden. It's too early. -Most decisions so far seem to be based on scientific evidence. -As far as I can tell there are good models, adjusted to local conditions but maybe not adjusted to Corona yet My guess* is that the lack of data makes it hard to run the models with a valid set of parameters, models have been proven to work in other situations may or may not produce good predictions. The models' predictions are open for various interpretations. Data in this early stage can support both a lockdown and an open strategy; there is an overlap. Both may be sound scientific interpretations, there are scientists (and others) on both sides in the discussion. I can't guess if this policy will have a good or bad outcome. But I can see the logic behind the attempt to balance for instance: -Base decisions on local conditions, not so much on what others have done. -Try to close down enough to allow for health care to cope and adjust. But do not close down more than that. -Try to make recommendations that people will choose to follow over an extended period of time, it is not a three weeks sprint run for a vaccin. There are lots of other observations to add but that would turn this into blog post. If there is interest in some specific aspect I'll try to answer or find sources. *) I do not have studied the numbers and methods enough claim any insight (yet).

Bmpbmp1975 has been banned for spamming, after an obscene number of warnings. We only needed one thread misunderstanding vacuum decay, thanks very much.

I think the need was never in question (as well as for the other treatments). Due to the ongoing situation, often the designs are less than optimal and/or part of emergency/mercy treatments. I have a hard time imagining how it would work. Most of the viral particles are not just sitting on tissue, but are inside the cells (or after leaving cells would circulate). I would assume radiation that is damaging to them, would also be harmful (probably more so) to live tissue. After exiting they also disseminate via body fluids so point sterilization does not seem to be the right strategy to me.

Since the volume of of fluid is taken as constant The left hand side tells you that the time rate of heat flow into the fluid in the bath time rate of heat flow =( mass of fluid times specific heat) * ( the time rate of change of temperature of the fluid) time rate of heat flow =(volume * density * specific heat) * (the time rate of change of temperature of the fluid) time rate of heat flow = [math]\left( {V{c_f}{\rho _f}} \right)\left( {\frac{{\partial u}}{{\partial t}}} \right)[/math] This is not part of the conduction equation of the bar. But the conduction equation of the bar does give the quantity of heat passing through any cross section of the bar, as a function of the distance along the bar. Formally it says that the time rate of heat flow through a section is proportional to the area of cross section and the temperature gradient at that section or time rate of heat flow through a section = (a constant) * (area) * (temperature gradient) time rate of heat flow through a section = [math] = \left( { - {K_0}} \right)*\left( A \right)*\left( {\frac{{\partial u}}{{\partial x}}} \right)[/math] The constant K0 is called the thermal conductivity and taken as positive, from its use in other situations. Since heat flows from a higher temperature to a lower one this introduces the negative sign. Equating these rates of heat flow leads to the equation shown. The hint tells you to find a solution to the for the temperature u at x = L.