Sensei

What is doable is placing mirrors/filters in cosmic space between the Sun and our planet, and this way disallowing too large radiation to arrive to planet surface. Filters which will just reflect, or reflect and harvest energy to use it by human population. Polarization filter reflects 50% and pass through remaining 50%. Two polarization filters, one by another, with adjustable angles can allow remote control how much of energy arrives between 50%..0%. There are two types of reactions endoenergetic and exoenergetic (endothermic and exothermic). One requires input of energy from external source, other one is releasing energy to environment. Either nuclear fusion is releasing energy, and nuclear fission is releasing energy. Photodisintegration, or creation of free neutrons, are examples of reactions in which missing energy required to split nucleus is arriving from external source. To "remove" Carbon-12 or Oxygen-16 atoms from the core of the Sun, you would need even more energy to split them. It's called induced radioactivity. (rest-mass of C-12 nucleus + rest-mass of He-4 is higher than rest-mass of O-16) How to prevent burning of Helium-4, Carbon-12 or Oxygen-16 etc. in the core of star? Decrease core temperature. At lower temperature there will be less reactions per second happening. Extremely tricky business. One mistake in calculations and there can be too much decrease of temperature and everybody would die in global ice age.

Introduction of Iron, or some few other heavier elements, indeed can decrease temperature inside of the core of the Sun. But I am afraid so, there is not enough of Iron in the entire Solar system to do it on mass scale. Fe+Fe requires energy to fuse together (and product Te-108 is not stable). That energy is taken from core decreasing its temperature, and regular fusion processes are stopped. If it is happening rapidly, outer layers of star, collapses toward core. They accelerate to significant or even relativistic velocities.. What will happens next depends on their velocity/kinetic energy. During collision of outer layer particles with remains of core particles there can be created pair of electron-positron, or neutrons, photodisintegration, and other high energy physics reactions. That's what happens in various types of nova/supernova explosions. Fission is releasing energy.. It's not what will happen inside of so small star as the Sun. Problems with the Sun will start when 3x He-4 fuse together to make C-12. And then C-12 will fuse with He-4 to make O-16. And so on. It's not in even close to fissile elements..

What are you talking about.. ? What text file? Audio files are binary files, mostly compressed one.. Only raw format could be reversed by reversing order of bytes in file, as long as you know how many bytes per sample is (usually 1 or 2), and how many channels (usually 1 or 2), and byte order (Intel-compatible or Motorola-compatible). .wav file format has header at the beginning of file. If data are not compressed (wFormatTag set to WAVE_FORMAT_PCM), it would be 2nd the easiest (after plain raw format) to reverse in custom made script. 5-10 minutes to write it or so. https://docs.microsoft.com/pl-pl/windows/desktop/api/mmreg/ns-mmreg-twaveformatex Yes.

Try editing it in Macromedia Flash Editor, or Adobe Flash Professional CC or similar flash editor..

Majority of video file formats to compress more efficiently utilize key frames and intermediate frames. Key frame contains entire compressed image. Intermediate frame contains relative data from the last key-frame or key-frame with applied changes (previous frame). When difference between raw frames is too large, it's the more efficient to store key-frame (with the all image data), rather than relative data. To play backward codec must find previous key-frame, and generate intermediate frames from it. Video file format can contain entire table of the all key-frames (usually at the end of file). Key-frames can have special unique codes to allow codec to find them manually in stream of data. i.e. file.seek(random_position ); file.read(buffer,len); search in buffer for codes.. https://en.wikipedia.org/wiki/Key_frame "In video compression, a keyframe, also known as an "intra-frame", is a frame in which a complete image is stored in the data stream. In video compression, only changes that occur from one frame to the next are stored in the data stream, in order to greatly reduce the amount of information that must be stored. This technique capitalizes on the fact that most video sources (such as a typical movie) have only small changes in the image from one frame to the next. Whenever a drastic change to the image occurs, such as when switching from one camera shot to another, or at a scene change,[1] a keyframe must be created. The entire image for the frame must be output when the visual difference between the two frames is so great that representing the new image incrementally from the previous frame would require more data than recreating the whole image. Because video compression only stores incremental changes between frames (except for keyframes), it is not possible to fast forward or rewind to any arbitrary spot in the video stream. That is because the data for a given frame only represents how that frame was different from the preceding one. For that reason, it is beneficial to include keyframes at arbitrary intervals while encoding video. For example, a keyframe may be output once for each 10 seconds of video, even though the video image does not change enough visually to warrant the automatic creation of the keyframe. That would allow seeking within the video stream at a minimum of 10-second intervals. The down side is that the resulting video stream will be larger in size because many keyframes are added when they are not necessary for the frame's visual representation. This drawback, however, does not produce significant compression loss when the bitrate is already set at a high value for better quality (as in the DVD MPEG-2 format)."

The easiest would be to load video file to some video editing software, such as e.g. VirtualDub, which you can download from http://www.virtualdub.org/ and use e.g. this tutorial: Tutorial shows that you can load video file, and export to image sequence. Then reverse order of files on disk and import image sequence back to program and compress to final video file. Google for "how to reverse video in [XXX]" where XXX is your video editing software. ps. .swf is not video file. It's ShockWave Flash file format.

Optimum design is having no windows at all.. It's unneeded complication in airplane design, useless for any modern country traffic controllers. In 3rd world country, some old airplanes indeed might not have transponder installed. Easier to install transponder than redesigning body of obsolete airplane.

If you want to see how microorganisms grow up with time you will need Petri dish (quite inexpensive). https://en.wikipedia.org/wiki/Petri_dish After adding agar and nutrients, they will turn to "agar plate": https://en.wikipedia.org/wiki/Agar_plate

Everything depends on availability of money and your willingness to spend it.. You could buy him one of Bresser microscopes, which have LCD screen. They allow making photos, and videos, on demand, after clicking button, which can be uploaded to e.g. YouTube or Vimeo. Data are stored on memory cards, or transferred directly to computer through USB. This one costs here $240:

If you are interested what is ID of some airplane, especially when it's flying, you can use FlightRadar website: https://www.flightradar24.com/ There is a few seconds delay what is displayed on the map, and the real world. When the next time you will see airplane in air, open website, and you will see how far it is from you versus where it is on the map on the website.

I know what was the question. I started from explaining how to get grayscale, or black & white image, in the first place, from point of view of mathematics. From equation with three unknown variables (r,g,b) there is made just single one (luma). Luma is known, from photo, but you can't return back automatically to having r, g and blue back. Information has been lost. That was purpose of my post. To show that information has been lost. Hand painting of the real photo would require quite a bit of experience. You would have to mix various base colors, in the right proportions, to get intermediate one.. Entertaining for some people. I would use computer program of course. Less messy and more control to manually color grayscale image. Put grayscale image in background layer, and make new layer with color on top of it, and change layer blending mode to "multiply". Then use brush tool. grayscale * base color = final color. You can search for colorful reference image, on the net, load it as second project in application, and pick reference color ("color picker tool") of some common elements like color of human face, tree, grass, sky, etc. etc. For a start to learn how to do it, you can find colorful photo, duplicate it, and use convert to grayscale tool. Then you have either colorful version of project and grayscale version of project at the same time in computer painting program. Then use color picker tool on reference colorful version to get color, and try recreating colors in grayscale version of project, using the above mentioned method. If you know exact location where photo has been taken, you can go there and make photo again, or use Google Maps in 3D "Street View" mode, and use it as reference color for background environment. Then you will have to recreate just colors of people.

How to get gray from RGB? The easiest function is: luma = ( red + green + blue ) / 3 (each component has the same influence) The more complex function utilize specific influence of component on gray scale: e.g. luma = 0.2126*red + 0.7152 * green +0.0722 * blue For more coefficients look at https://en.wikipedia.org/wiki/Luma_(video) https://en.wikipedia.org/wiki/Grayscale Literal B&W (black & white), is even worser, it has only black and white pixels without any other intermediate pixels.. Grayscale is just simulated by dithering. Now you come by, and ask for information, which has been removed/deleted from image, and want to get it back.. ? You need to manually color tint images https://en.wikipedia.org/wiki/Hand-colouring_of_photographs google for "color tinting images" or so..

Did you read this article prior writing forum question? https://en.wikipedia.org/wiki/Invertible_matrix

The easiest to model is linear evolution of physical variable. Read some physical variable x0 at time t0, Read physical variable x1 at time t1.. Equation can look like: f(t)=x0+(x1-x0)/(t1-t0)*t or f(t)=x0+dx/dt*t where dx=x1-x0 and dt=t1-t0 Similar easy to model is constant acceleration, and constant deceleration. Calculation of leaf falling from tree would be extremely hard, because each object has different terminal velocity, which depends on e.g. mass and shape of object, and angle of object while traveling down.. https://en.wikipedia.org/wiki/Terminal_velocity It would be easy to model only in scenario with vacuum.

Search Amazon, eBay, Google and Ali etc. for "optical bench".. It allows precise placement of optical elements, in exact positions, from light source, one by another, and observation and measurement what happens with light beam during passing through various filters which you put on laser/light path.

I bought setup in local educational store. I don't want to encourage you to buy something I didn't test by myself. But here you have some double slit (x4 versions) on Amazon: https://www.amazon.com/Diaphragm-Double-Slits-Different-Spacings/dp/B00KWZ5WQ0 (very wide...) You will also need laser pointers red, green and blue. It would be also good to have diffraction grating filters, and polarization filters (at least couple). Search for it by yourself.

Do you have double slit experiment apparatus.. ? To repeat it by yourself at home.. ? You should buy it. It's pretty inexpensive (as long as it's done with photons, not electrons, or other particles). It cost $20 here, for pair of laser + double slit filter with fixed holes. (it would be better to have red, green, and blue lasers, with couple different slits setups).

Borax is also salt.. salt of boric acid. Humility didn't say which salt had on mind. Didn't say "kitchen salt".. Initial post can be interpreted as: "if I took salt ("...from such salt lake which evaporated..." *), dumped it in a pot of water, boiled the water away, then refilled and repeated, would I eventually wind up with borax? " *) it is implied by the first sentence of post..

It's called binocular vision, common to predators: https://en.wikipedia.org/wiki/Binocular_vision In contrary to monocular vision, common to herbivore living organisms: https://en.wikipedia.org/wiki/Monocular_vision I have no idea why are you introducing some consciousness and subconsciousness here.. nor why are you limiting it to human.. Dog or cat can also listen to you from other room, and run to you if you will call him/her by name. Animals recognize by look, by voice, by smell, by touch. Typical methods of communications of living organisms. Like human. Whales are using echolocation on great distances. https://en.wikipedia.org/wiki/Animal_echolocation Whales songs can travel for thousands kilometers. https://en.wikipedia.org/wiki/Whale_vocalization ps. It reminded me that people who have dog which is badly missing owner (and is loudly barking which is annoying for neighborhood), are using apps on smartphone/tablet, to talk through Internet to their animal friend. Dog hears and sees owner on the screen and is more polite.

"Borax occurs naturally in evaporite deposits produced by the repeated evaporation of seasonal lakes." "Naturally occurring borax [...] is refined by a process of recrystallization." Reference https://en.wikipedia.org/wiki/Borax Search Google for compounds solubility (or solubility curve with temperature), in water, or other solvent. Compare them to find the largest difference.

How big is 1.. ? How big is 100.. ? How big is any other number.. ? I don't think so word "big" applies here. It would make more sense, if there would be second reference number to which zero is compared.. "0 is bigger than -1" "0 has just one digit required to write it in any numeral system". (only 0 and 1 fulfill this. To write down 2 in binary system there are needed two digits %10) "irrational number has infinite number of digits required to write it in any numeric system". 0 is not irrational number.

12 kV = 12000 V 1 micro amp is 10^-6 A 12000 V * 1*10^-6 A = 0.012 W (10 times less than 0.12 W). If "incandescent Christmas light" has 0.12 W * 3 = ~ 0.36 W, then 0.36 W / 0.012 W = 30 wires needed.

Immortalized cells can flow with blood and spread on entire body. I didn't say there will be no cure. I said there is no uniform medicament for everybody. Cure must be unique to person/cancer they have. It's better to prevent cancer, than having to cure it when it appeared..

What is the most important in cancer is whether cell became "immortal".. "immortal cells" don't act like regular cells, which die after too many divisions.. https://en.wikipedia.org/wiki/Henrietta_Lacks https://en.wikipedia.org/wiki/Immortalised_cell_line Cancer is no disease as other, so there can't exist universal cure, which will work for everybody.. It's not bacteria, nor virus... To cure normal disease there is needed medicament which will attach to bacteria cell or virus, outer molecule, and this way they will be identified by immunology system cells. Cancer is random mutation of random cell DNA, giving random cancer cell. By immunology system it's treated as regular body cell. Each cancer is unique (unless somebody had transplantation of organ from ill person). "Breast cancer" of one woman is not the same as "breast cancer" of other woman. The only the same is placement of cancer. If cancer cell will be taken from body, and immunology system cells will be learned, that they should fight with it, they will do it. But it'll have to be repeated for every single ill person.

I gave such advice in the past.. ..but it's enormous amount of work required... ...but people are even unable to fight global warming here on the Earth.. some even rejecting it's even happening...