General and Special Relativity

Light has mass since it has energy.

Energy depends on the wavelength/frequency.

Einstein and Planck get credit for working this out.

Using red light of wavelength 650nm travelling in a vacuum we get a mass of 3.4x10^-36 kg. The weight depends on the gravity, but on Earth that would weigh roughly 3.332x10-35 N.

That depends on what is burning. If it's something normal like wood, the coloration is attributable to the changes in temperature as the flame moves away from the fuel.

In other cases, such as a hazardous material, the color can be orange, green, blue, purple depending on the fuel...One things sure though! You don't want to be ANYWHERE near a flame that's any color other than orange!

The question "What is the meaning of life?" is subjective and philosophical, and thus has no definitive answer that applies universally. Each individual may have their own interpretation or belief about the meaning of life.

Convex lenses are thicker in the middle than at the edges. They refract toward the center. Only people have convex lenses. Concave lenses are used in telescopes and glasses. Concave lenses are thinner in the middle than at the edges. When light passes through concave lenses always bend away from each other toward the edges of the lens.
A convex or "positive" lens is thicker in the middle and thinner at the edges. A concave, or "negative" lens is thinner at the middle and thicker at the edges. Convex lenses project a real image behind the lens; concave lenses project a virtual image in front of the lens.

no, unfortunatly. time travel is more of a fantasy or somthing interesting to put in a story.

Well, Although that that statement could be true ^^^ There is the fact that we just haven't invented it. We might not even need a Flux Capacitor. I mean we might have it in near future although it doesn't need to be a fantasy. Hope this helps.

Einstein completed the theory in November 1915 and published it the following Spring.

Einstein's theory of relativity is a fundamental theory in physics that describes the relationship between space and time. It consists of two main parts: the special theory of relativity, which deals with uniform motion, and the general theory of relativity, which extends the theory to include gravity. The theory has important implications for our understanding of the universe, particularly at very high speeds or in the presence of strong gravitational fields.

Time dilation is a phenomenon in which a person finds a clock or other time device similar or identical to their own ticking at a slower pace; therefore making the observer believe that time has "slowed down" for the other clock; but in actuality, time passes at a constant rate; it just true for the observer's frame of reference.

Part 1: General relativity has gravity act on photons not directly (as with objects with mass) but by bending the space&time around the object. The photons are unaffected. The path they take is curved, so they appear to bend. Sort of like how you can walk in a "straight line" on earth, but eventually appear where you started. Because the earth is curved, your path is curved, it has nothing to do with how much mass you have.

Now there is a way to describe reflection and refraction using only photons, and that process is described below by other posters:

The process of reflection/refraction is really a process of absorption/emission on a really small level. When electrons, say those of silicon atoms, are bombarded with photons, they absorb their energy, and, quite temporarily, the photon ceases to be observable as light.

The electron then immediately emits a photon in the opposite direction, producing the illusion of light moving more slowly; however, we know that the speed of light is constant in every possible scenario, even outside a vacuum. This just happens to be one of the strange consequences of the quantized state of matter at the sub-atomic level.

An atom is a system which wants to exist in its ground state. It does not want to absorb the energy of a photon and thus, it ejects the energy in the form of a photon (the energy difference as a result of the "collision" is manifested in a slight change in the wavelength/frequency of the emitted photon)

Very good answer above, for further information on electron reflection/diffraction, Richard Feynman has some excellent free video lectures on QED that were intended for the layperson.

Answer2:

Photons have mass and the concept of rest mass is false.

Daring to challenge General Relativity, Photon's have mass W = hf = pc = mcc, thus m=hf/c2= h/cw and thus is affected by gravity.

Einstein's Deflection 1.7" is the result Gravity tan D= .5gt2/150Gm = .5 x9.8 x150G/c2=8.16666E-6 ,

where t= 150Gm/c and g= 9,8 earth's gravity.

Answer 3: There is a reason why gamma, X-ray, Bharat Radiation, and light photons attract towards Earth. Both energy and matter constitute three components: electric, magnetic, and gravitational. In clear words, since photon's gravitational component facilitates attraction towards Earth.

Because strong people can force their will on the weak. Being tough gives them the feeling of control (even in situations where the power is not actual).

There are many methods to force your will on others (control):

Money

Physical strength

Reputation

Common interests

Common enemies

Morality

Debt

etc...

All people want these things in differing amounts. Toughness is just one of the normal mechanisms for controlling other people.

The word "mischievous" is often mispronounced as "mis-CHEE-vee-us" by many English speakers, when the correct pronunciation is actually "MIS-chiv-us" with the stress on the first syllable.

Of course not...different densities, different volumes per same weight.

According to the theory of relativity, time dilation occurs as an object's velocity approaches the speed of light. As a result, time will appear to pass slower for you as you travel near the speed of light compared to your twin who remains on Earth. Therefore, when you eventually reach your twin, they would be older than you.

It depends on what these invariant quantities are. It is not enough to specify that something is invariant, you also need to specify under which operation these quantities do not change (= are invariant).

In special relativity there is an operation called a Lorentz transformation which applies the effects of a speed increase, thus applying time dilatation and length contraction. A Lorentz invariant quantity is a quantity which remains the same under this transformation, i.e. it has the same value for every observer in an inertial frame.

Examples of such invariants are the lengths of four-vectors, the generalizations of the common 3-dimensional vectors such as those indicating place and momentum. For example the 3d-vector for location (x,y,z) is joined with another quantity for the time dimension into a 4-vector whose length is Lorentz invariant. There are more Lorentz invariant quantities, some of them quite complex.

It's (double the photon's energy) divided by (the speed of light squared).

The photon's energy depends on its frequency, and is (frequency) times (Planck's konstant).

The twin paradox is a thought experiment in special relativity that involves one twin traveling at high speeds and the other twin staying on Earth. The twin who travels at high speeds will age more slowly relative to the twin who stays on Earth. However, this does not directly affect human metabolism as it primarily involves differences in time dilation and perception of time. Metabolism is a biological process that is influenced by a variety of factors such as diet, exercise, genetics, and overall health, rather than the effects of relative motion and time dilation.

Its value grows to become precisely equal to double its initial value,

while its direction remains unchanged.

Yes, light can bend around objects. This phenomenon is known as diffraction and occurs when light waves encounter an obstacle or a small opening. Diffraction causes the light waves to spread out and bend, allowing us to observe patterns such as the bending of light around the edges of a solid object or the interference patterns produced by a narrow slit.

We do experience a form of time dilation in everyday life, but the effects are extremely small. Time dilation occurs due to differences in gravitational potential and velocities. In our daily lives, these differences are relatively insignificant compared to extreme situations, such as near a black hole or moving at speeds close to the speed of light, where the effects of time dilation become much more pronounced.

If the density of a substance is less than the density of water (1 g/cm^3), then it is likely to float. If the density is greater than 1 g/cm^3, it will likely sink. However, the shape and size of the substance can also affect its buoyancy, so it's important to consider other factors as well.

Assuming all of the objects have the same mass, the answer depends on their combined velocities. If the combined vector component of velocity of two objects is the same as the velocity of the single moving object, then the force of impact will be the same. So if the two are moving in opposite directions along the same path, they will generate the same amount of force as a single object moving at a velocity that is equal to the combined velocities of the two. If the velocities are different, the force varies accordingly.

• it is a constant that is determined by Maxwell's equations for the speed of all electromagnetic radiation traveling in a vacuum.
• it is the same for all observers in all reference frames in special relativity. in agreement with Maxwell.
• nothing can travel faster than that speed. it is the speed limit.

Watts, same as light bulbs. Most pen pointer lasers are 5 mw, or 5 milliwatts (5 thousandths of a watt). Image the light of a 120 watt incandescent bulb compared to that. 120 watts vs. 0.005 watts. The light bulb consumes 24,000 times more energy, even though the laser dot is really, really bright.

The theory of relativity consists of numerous mathematical equations and concepts that describe the behavior of space, time, and gravity. It is not possible to determine the exact number of words in the theory as it is primarily expressed in mathematical notation rather than words. However, there are many books and papers written about the theory of relativity that explain the concepts in words.