Introducing Green Venus
Imagine a world that I will call "Green Venus" (I was tempted to call it "Forks" after the very cloudy town in Washington State, but decided against that.)
Like our planet Venus, it has a nearly circular orbit around its star with an orbital period in the same time range of Earth and Venus, it doesn't have a moon, it has no detectable magnetic field, it is geologically active, it is located in the "habitable zone" from its star, it is similar in gravity and size to Earth, it is a terrestrial planet with a continent sized solid surface, it has clouds that admit heat.
While enough light makes it through the clouds on most days to reveal the star's location and to be similar to that of a cloudy day on Earth from its star, it is rarely clear enough to allow someone on the surface to see the stars or planets. The sunniest mountain top on Green Venus gets a few hours at a time when the clouds do not conceal the sky a couple of times a year, and more brief glimpses of the sky free of cloud cover that may last just a few minutes, every two or three weeks. Most places on Green Venus go decades between several minute long glimpses of the sky not obscured by clouds.
Like Earth, and unlike the real planet Venus, it does not have a retrograde orbit, it rotates around its axis roughly once every twenty-four hours. It is mountainous and geologically active to a similar degree to Earth. None of the elements that do not naturally occur on Earth, like Technetium and elements with atomic numbers of 93 or greater, are found in nature on Green Venus. It has surface temperatures that are similar to, but slightly less extreme than those on Earth. On the surface of Green Venus it is never more than about 40 degrees centigrade and never less than about 20 below zero centigrade (without considering windchill). Green Venus has large and deep oceans of salt water that cover most of its surface, it has many fresh water lakes and rivers, and it has an atmosphere essential identical to Earth's in chemical composition and surface air pressure. The greenhouse effect created by its clouds is balanced by a combination of its distance from its star and the size of its star. Green Venus is not as tilted on its axis relative to the plane in which it orbits as Earth and has a more circular orbit and few tidal influences, so it experiences considerably less seasonal variation than Earth. Like Earth, large swaths of Green Venus are thick with vegetation and animal life, and even the most hostile environments on the planet support life of some kind.
Critically, millions of years of intense struggles to survive in the face of natural conditions and fierce predators have produced a species of highly intelligent life on Green Venus that has become the dominant species on the planet with a vast, flourishing and sophisticated civilization.
In short, Green Venus is a lot like humans imagined that it would be until we sent some probes there and discovered just how ugly a place to live it was under its toxic clouds.
Unlike our solar system, there are no gas giant planets that orbit the same star as Green Venus, and it is the only terrestrial planet orbiting its star in an inner orbit. There are asteroids, comets, and dwarf planets that orbit at a distance comparable to Pluto, but the largest planets also happen to be not very reflective. The outer region of this solar system is full of interstellar dust and gas, as is a large swath of interstellar space between this solar system and the closest galaxy around which its star rotates at a much greater distance from the galactic center than Earth. The closest star to Earth is about 4.3 light years away. The closest star to Green Venus is about 43 light years away and has an absolute magnitude of about 2.6. All stars are obscured from the perspective of Green Venus by a large region of dust and interstellar gas that is relatively clear only in the inner solar system around Green Venus. As a result, even from orbit above the clouds of Green Venus, there are far fewer bright stars and planets in the sky visible to the naked eye than there are from the surface of Earth on a clear day.
While Green Venus has a very similar atmosphere and set of oceans to Earth, the minerals on Green Venus that are accessible on the surface of the planet or through mining are different. Green Venus has been home to life only about as long as Earth had during the Carboniferous period, so it has far fewer hydrocarbon deposits (e.g. peat, coal, oil and natural gas) than Earth. Green Venus also has far fewer heavy elements, such as platinum group metals, as well as far less gold, silver, mercury, lead, and Bismuth. Natural diamonds are several hundred times more rare on Green Venus than they are on Earth, with gem sized diamonds also being disproportionately more rare relative to deposits on Earth than tiny ones.
Green Venus no deposits of heavy radioactive elements like Polonium, Astatine, Francium, Radon, Thorium, Protactinium, or Uranium in its surface crust where they can be accessed by mining. No element with atomic number 84 or greater is found in nature in any accessible part of Green Venus, and elements with atomic numbers higher than 74 (Tungsten) are profoundly more rare than they are on Earth on Green Venus.
I pose this as a hypothetical, but such planets probably exist. Stars in voids between filaments of dark matter have very low heavy metal content and very sparse stellar density.
What Kind of Science Would Green Venusian Develop?
The highly intelligent Venusian's who were in a fiercely competitive environment would clearly have reached a quite sophisticated level of scientific advancement. In all areas of inquiry available to them, from mathematics, to social sciences, to organic chemistry, and so on, they would excel. But, this environment would still produce a very different kind of scientific advancement than our actual history on Earth has produced.
Obviously, Green Venus would have much less sophisticated astronomy. It would not have general relativity. Newtonian gravity, modified to allow it to bend light, would be a cutting edge and controversial development comparable to quantum mechanics and general relativity for us, while most scientists would describe the phenomena of gravity with a formula consisting of formula relating gravitational pull based upon your weight and altitude relative to sea level, and would cling to a Venus centric view of space that is rooted in an ancient myth.
Nuclear fission power plants would be impossible without sufficient deposits of radioactive fuel, and the study of weak force decays would be much less advanced and much less a part of the scientific consciousness. The lack of access to naturally active isotypes would also probably impair the development of nuclear physics generally, although QED would still probably be known to scientists and engineers and used daily by engineers and scientists. Beta decay wouldn't be entirely unknown to scientists, but particle physics would be numerous decades behind.
The Venusians would probably have a proton, neutron, electron model of the atom and something closely approximating the periodic table, although with far fewer elements.