If string theory were to be ultimately unsuccessful or disproven, it wouldn't necessarily mean that string theorists have to return all the funding they received. Scientific research, including theoretical physics, involves exploring various hypotheses and ideas in the pursuit of knowledge and understanding. Not all theories or research directions yield successful outcomes, but that doesn't necessarily invalidate the process or imply any wrongdoing.
Funding for scientific research is typically provided by institutions, organizations, or grants based on the potential value and significance of the research proposal. The decision to fund a project is often made based on the merit of the proposal and the expertise and reputation of the researchers involved. If a research project fails to achieve its intended goals or doesn't yield the expected results, it's generally not considered a crime or an ethical violation.
The scientific process involves taking risks, exploring different avenues of inquiry, and acknowledging that not all hypotheses will turn out to be correct. Failure and the ability to learn from it are an integral part of scientific advancement. Funding agencies and institutions understand this inherent uncertainty and expect that some projects may not yield the desired outcomes.
Furthermore, string theory, despite its challenges and complexities, has made significant contributions to our understanding of fundamental physics. It has provided new insights, mathematical frameworks, and connections between different areas of physics. Even if string theory were eventually proven incorrect or incomplete, the knowledge gained from pursuing it would likely have value and influence future research directions.
It's important to recognize that science is a collective effort, and progress often emerges from the accumulation of knowledge and the exploration of various ideas, even those that may ultimately prove to be incorrect. The scientific community operates under a system of peer review, where ideas and theories are subjected to scrutiny and evaluation by experts in the field. This process helps ensure that resources are allocated based on the potential scientific merit of the proposals.
In summary, if string theory were to be disproven, it would not necessarily lead to researchers having to return the funding they received. Scientific research is a complex and iterative process, and failure to achieve a specific outcome does not constitute a crime. It is through this process of exploration and learning that scientific knowledge advances over time.