Albert Einstein was a physicist and mathematician who made significant contributions to our understanding of the universe. While he was not an inventor in the traditional sense, his theories of relativity led to new ways of looking at time, space, matter, energy, and gravity, which in turn inspired important advances in various fields. Here are some of his key scientific contributions and discoveries:

• The quantum theory of light: Einstein proposed that light is composed of separate packets of energy, called quanta or photons, that have some properties of particles and some properties of waves. He also explained the photoelectric effect, which is the emission of electrons from some solids when theyre exposed to light.

• Brownian movement: Einsteins findings helped to prove the existence of atoms and molecules by studying the zigzag motion of microscopic particles in suspension.

• The special theory of relativity: Einsteins third paper published in 1905 offered his special theory of relativity, which describes the relationship between space and time.

• The general theory of relativity: Einsteins fourth paper published in 1905 led to the development of the most well-recognized equation in science: E = mc². This equation, and his other theories, helped in the development of the atomic bomb, though Einstein was never asked to participate in the American-led atomic weapon effort called the Manhattan Project.

• Avogadros number: Einstein contributed to the concept in chemistry that defines the number of units in one mole of a substance.

• Bose-Einstein condensate: Einstein predicted the existence of this state of matter, which was later discovered in 1995.

While Einsteins scientific discoveries and inventions have had very few drawbacks, they have had a significant impact on our understanding of the universe and have contributed to the development of numerous technologies.