This blog post introduces various theories of the multiverse through ‘The Hidden Reality’ and discusses whether these theories are truly worth studying.
Brian Greene’s book ‘The Hidden Reality’ introduces various forms of multiverse hypotheses currently debated among scientists. Many of these hypotheses are difficult to grasp with common sense, and it remains impossible to verify which, if any, are correct. Consequently, the author poses the question midway through the book: “Is it truly worthwhile to explore a multiverse that cannot be applied to real life and whose truths cannot be verified?” Indeed, when the Laser Interferometer Gravitational-Wave Observatory (LIGO) successfully detected gravitational waves on February 11, 2016, massive investments were made—including building LIGO, which is over 4 kilometers long—despite the lack of immediate practical applications for the discovery. There was a common argument that such investment overvalued the subject of research, and criticism existed that this scientific exploration was worthless. However, I wish to clarify that this argument stems from a misunderstanding of the process of scientific development and that evaluating the value of science is extremely difficult.
First, the criteria people primarily use when labeling exploration or knowledge as worthless science can be broadly categorized into three types. First, when there is no current practical application or the expected practical application of the research outcome is low. Take multiverse theory as an example: even if a multiverse theory were to become reality, such knowledge would likely contribute little to improving our standard of living. A similar situation arises when the benefits obtainable from science are low relative to the costs invested in it. For instance, the European Organization for Nuclear Research (CERN) operates a particle accelerator 27 kilometers long, maintained at an internal temperature of minus 271 degrees Celsius. Given the astronomical costs of maintaining and operating such facilities, some argue that research topics like string theory or dark energy, deemed to have little practical value, should cease as worthless science.
Second, there are cases where theories can be formulated and knowledge systems built, but no means exist to verify them. Multiverse theory presents various competing theories, yet no proper verification methods exist to prove these claims. This is because most multiverse hypotheses assume it is impossible to transition from one universe to another. For example, in the patchwork multiverse, the fundamental premise is that the universe is infinitely large, making it impossible to detect parallel universes. In the Bubble Multiverse, universes are separated by an inflaton field, making travel between them impossible. The Braneworld Multiverse would gain significant credibility if string theory were verified, but even verifying string theory itself faces immense difficulties. Some argue that no matter how plausible these theories seem, they hold no value because verification itself is impossible.
Third, the research purpose of science deviates from public interest and serves only the personal curiosity of individual scientists. Multiverse theory research often originates from the intellectual curiosity of individual scientists rather than being driven by specific plans or social contributions. Some argue that such exploration, which follows the personal interests of scientists rather than being systematically conducted to alleviate societal discomfort or advance human welfare, is worthless and warrants reconsideration of research funding.
These three main arguments describing the exploration of the multiverse as worthless stem from a misunderstanding of the process of scientific development. Examining how science has advanced throughout history reveals that the value of scientific knowledge or inquiry cannot be judged immediately, either during the research or after the knowledge has accumulated. Numerous historical examples exist where scientific knowledge only came to light due to advancements in surrounding technology.
Regarding the first argument—that something has no value if it lacks practicality—consider Einstein when he first presented the theory of relativity. Since relativity theory only demonstrates effects in situations requiring extremely high speeds or gravity, contemporaries likely believed it had little practical application. However, modern GPS relies on significant gravitational differences between satellites and users. Due to GPS’s requirement for high precision, it must account for the time dilation effect described in general relativity. Therefore, time correction is necessary to synchronize time between satellites and the Earth’s surface.
The second claim—that if something cannot be verified, it has no value—may seem similar to Karl Popper’s assertion that “a scientific proposition must be capable of substantive verification to be accepted.” However, a scientific proposition that remains unverified or lacks clear verification methods cannot be deemed worthless forever. This is because what was thought unverifiable when scientific knowledge first emerged can later become verifiable through advancements in related sciences. When Democritus claimed all matter consists of indivisible particles, there was no way to prove it at the time. Yet in modern times, atomic theory has been proven through various verification methods.
Third, regarding the claim that science driven by scientists’ interests is worthless, research achievements across diverse fields and knowledge that has become practical for humanity often originate from scientists’ interests. Take electromagnetism, which became the driving force of modern society—it began when Michael Faraday, during an electrical experiment, noticed a nearby compass needle moving and found it intriguing. While a scientist’s curiosity may seem like grasping at straws, such actions cannot be dismissed as lacking potential.
Thus, we have refuted these three arguments that deem science worthless. Research into parallel universes and the multiverse may appear worthless from certain perspectives, yet our understanding of the universe remains profoundly limited. Therefore, evaluating theories like the multiverse with short-sightedness and dismissing their value is highly premature. Society must adopt a broad perspective and carefully assess the value of science. From this perspective, no scientific knowledge or theory currently under investigation can be deemed worthless. Therefore, the general public and public opinion should not view scientific research pessimistically simply because they lack full understanding; instead, they must accurately grasp its value and importance.
