It's impossible to name *the* scientist who caused the most controversy that still exists today, as many have made impactful discoveries or voiced opinions that sparked ongoing debates. Here are a few examples of scientists whose work or stances continue to be debated:

1. Charles Darwin: His theory of evolution by natural selection revolutionized biology but continues to be challenged by religious groups and some scientific communities. Debates center on the role of intelligent design, the completeness of the fossil record, and the validity of evolution as an explanation for the diversity of life.

2. Albert Einstein: His theories of relativity laid the foundation for modern physics but have also led to ongoing debates about the nature of space, time, and gravity. His work inspired research in cosmology and quantum mechanics, fields still grappling with fundamental questions and paradoxes.

3. Marie Curie: While celebrated for her groundbreaking work in radioactivity, her research also led to controversies surrounding the ethical use of radioactive materials. The potential dangers of radiation became evident later, sparking debates about the balance between scientific progress and human health.

4. James Watson: Co-discoverer of the structure of DNA, Watson has been embroiled in controversy for his racist and sexist statements. His views have cast a shadow on his scientific contributions and highlight the complex relationship between scientific achievement and personal beliefs.

5. Robert Oppenheimer: Known as the "father of the atomic bomb," Oppenheimer was deeply involved in the Manhattan Project, leading to ongoing ethical debates about the use of nuclear weapons. The development of atomic bombs sparked debates about the responsibilities of scientists, the role of government in scientific research, and the potential for devastating consequences of scientific advancements.

6. Dr. Anthony Fauci: As a leading immunologist and advisor to the U.S. government, Fauci has been at the center of the COVID-19 pandemic response. His public health recommendations have sparked controversy, with some accusing him of being overly cautious while others praise his scientific expertise.

These examples demonstrate that scientific discoveries and the role of scientists can be deeply intertwined with social, political, and ethical debates. While some controversies have subsided, others remain active and continue to shape our understanding of the world and our place in it.