The Law of Falling Bodies (1600s)

Galileo Galilei (1564-1642), Italian physicist and mathematician, debunks the two-millennium-old Aristotelian theory that a more massive object falls faster than less massive ones, by proving that all bodies fall at a uniform rate of acceleration, provided that the air resistance remained insignificant or in the most ideal case of its falling through a vacuum. He expressed the mathematical equation for a falling body as follows: the distance traveled starting from the state of rest is directly proportional to the square of the elapsed time. Galileo’s quantitative experiments and theoretical studies on the motions of bodies, as well as the independent works of Johannes Kepler (1571-1630) and René Descartes (1596-1650), laid the foundation for the birth of modern science.

Universal Gravitation (1660s)

In his studies on gravitation and its effect on planetary orbits, Sir Isaac Newton (1643-1727), English physicist and astronomer, concludes that every object in the universe with mass exerts gravitational attraction on each other. The Law of Universal Gravitation was first formulated in his groundbreaking work “Philosophiae Naturalis Principia Mathematica” (published in 1687), “Principia” for short, stated as follows: the gravitational force between two bodies is directly proportional to the product of their masses, and is inversely proportional to the square of the distance between them. Newton demonstrated consistency between his gravitational theory with Kepler’s laws of planetary motion, by showing that movements of earthly bodies and of heavenly bodies are governed by the same natural laws, thus removing all opposition to heliocentrism and sparking the modern scientific revolution.

Laws of Motion (1680s)

Isaac Newton formulates three physical laws to describe the relationship between movement of objects and forces that act upon it, thereby radically altering our understanding of how the universe works. The three laws are often simplified as follows: a.) “An object will remain at rest or continue in motion unless acted upon by an external force”; b.) “The force on an object is equal to the mass of the object times its acceleration or F = ma”; and c.) “Every action has an equal and opposite reaction.” Newton’s laws of motion and universal gravitation, as expounded in his “Principia”, laid the foundation of classical mechanics that would dominate the scientific view of the physical universe for the next three hundred years and is the basis for modern engineering.

The Law of Thermodynamics (1820s-1850s)

In their effort to improve the steam engine efficiency, scientists were able to acquire an understanding of heat energy conversion into work, learning that heat energy flowing from higher to lower temperatures is what propels the steam engine. Their study led to the formation of the three laws of thermodynamics:

a.) Energy can neither be created nor destroyed, it can only be changed from one form to another, thus the total amount of energy stays the same

b.) The entropy of an energy system tends to increase over time

c.) As an energy system approaches absolute zero temperature, its entropy declines to a constant minimum.

These principles have become indispensable not only in the field of physics but also in other sciences as chemistry, chemical engineering, aerospace engineering, cell biology, biomedical engineering, and economics, to mention a few.

Electromagnetism (1810s-1870s)

In 1820, Hans Christian Oersted (1777-1851), Danish physicist and chemist, discovered the relationship between electricity and magnetism while preparing a lecture. He noted a compass needle deviated from the magnetic north whenever the electricity generated by the battery was alternately turned on and off. Further pioneering experiments by Michael Faraday (1792-1867), James Clerk Maxwell (1831-79), André-Marie Ampère (1775-1836) and other eminent scientists would further reveal the relationship between electricity and magnetism and led to the formulation of basic theories and laws governing them.

The Nature of Light (1700s – 1900s)

A greater understanding of the essence of light, and of its behavior and transmission was the result of theoretical thinking and experimental observation by Isaac Newton, Thomas Young (1773-1829) and Albert Einstein. Newton utilizes a prism to split light into its constituent colors; Young demonstrates that light behaved as waves and that colors are determined by their wavelengths; and lastly, Einstein proposes that light travels at a constant rate.

Special Theory of Relativity (1900s)

Albert Einstein (1875-1955), German-born theoretical physicist of Jewish descent, puts an end to the centuries-old accepted Newtonian theories of absolute space and time (or classical mechanics) by describing how time slows and distances stretch as a moving object approaches the speed of light.

E = mc2 (1900s)

Also known as mass-energy equivalence, stated as “energy is equal to mass multiplied by the speed of light squared.”  Albert Einstein’s famous equation demonstrates that mass and energy are but different manifestations of the same thing, and that mass, however small, can be exploited to produce massive amounts of energy. One inference of this discovery is that an object with mass cannot be accelerated beyond the speed of light.

The Neutron (1930s)

The discovery of the neutron by English physicist James Chadwick (1891-1974), together with earlier discoveries of the protons and electrons by Ernest Rutherford (1871-1937) and Joseph John Thomson (1856-1940) respectively, radically alters the atomic model and spurs rapid advancement in the field of atomic physics.

The Quantum Leap (1900s-1930s)

A new set of theories were devised by Max Planck (1858-1947), Albert Einstein, Werner Heisenberg (1901-1976) and Erwin Schrödinger (1887-1961) to describe the anomalous behavior of subatomic particles, giving rise to a new field called quantum physics. A quantum leap is defined as the instantaneous change from one energy state to another of an electron within an atom, resulting in the discharge of electromagnetic radiation. Quantum physics is an indispensable part of modern technology having wide-ranging applications that include laser generation, magnetic resonance imaging (MRI), transistor and electron microscope.

Superconductors (1910s-1980s)

The serendipitous discovery by Heike Kamerlingh Onnes (1853-1926) of certain materials that display properties of zero electrical resistance at very low temperatures, promises revolutionary transformation of modern industry and technology. The phenomenon of superconductivity can be found in a wide range of materials, including simple elements like aluminum and tin; and a  variety of metallic alloys and certain ceramic compounds; and has wide-ranging technological applications that include maglev trains, magnetic resonance imaging, particle accelerators, digital circuits, highly efficient power storage devices, transformers and electric motors, among others.

Quarks (1960s)

American physicist Murray Gell-Mann was the first to theorize the existence of elementary particles that combine to form composite objects as protons and neutrons, each of which contain three quarks. Quarks have six different types or flavors: up, down, charm, strange, top, and bottom.

Nuclear Forces (1930s-1950s)

The breakthrough discoveries and deeper understanding of the fundamental forces at work on the subatomic level brought about the true understanding that all interactions in the universe are the product of four basic forces of nature — the electromagnetic force, gravitation, the strong and weak nuclear forces.

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