Displayed in a sealed case at the National Archives Museum in Washington DC, the US Declaration of Independence is – alongside the Constitution, the Emancipation Proclamation and the Gettysburg Address – one of America’s most sacred documents. Just a single sheet of parchment, it was signed on 4 July 1776 by 56 representatives of 13 colonies, declaring themselves free of British rule. Even though years of fighting followed and Britain did not officially recognize the colonies’ independence until 1783, America dates its birth to that signing.

For many American citizens, the Declaration of Independence is greatly revered. I remember my grandfather had a copy mounted in the entryway to his home, and when I was 10 years old offered me $1 if I memorized it. I had no trouble with the start, for the document’s first sentence is arresting. “When in the Course of human events, it becomes necessary for one people to dissolve the political bands which have connected them with another”, decency requires that “they should declare the causes which impel them to the separation”.

The second sentence is equally exhilarating and unforgettable: “We hold these truths to be self-evident, that all men are created equal…”.  I didn’t discover until years later that this evidently didn’t include women, slaves, or the people referred to as “merciless Indian Savages”. Four truths later, the signatories zoomed in. When a government destroys “life, liberty and the pursuit of happiness” it is the “Right of the People to alter or abolish it”.

King George III was doing just that, they claimed, and the signatories followed with a laundry list of appalling grievances that amounted to tyranny. These included: obstructing justice, bending judges to his will, sending agents to harass and murder people, giving amnesty to those agents, transporting people overseas, cutting off trade with the rest of the world, making the military responsive to himself alone, and on and on.

Current US President Donald Trump claims that the Declaration of Independence led to “the greatest political journey in human history”. The document, he adds, set an example for the world. “The Story of America Makes Everyone Free,” he writes on an official website that has been counting down the days, hours, minutes and seconds to the 250th anniversary of the signing.

Destroyers of Earth

The enormous attention that the US administration is paying to this anniversary has made me wonder, however, whether a government today could destroy life, liberty and the pursuit of happiness badly enough to make it necessary to alter or abolish it. The answer was staring me in the face. What if it destroyed science enough to make citizens vulnerable to natural threats?

I’ve therefore been trying to imagine a revised declaration. Among the self-evident truths, I think, is that human beings are endowed with the right to protection against nature, that the purpose of science is to understand nature and its threats, and that a sovereign’s duty is therefore to foster science and act appropriately on its findings. A no-brainer, right?

These truths are more important than ever in the 21st century, I envision the document saying. Until recently in human history, nature could be treated as an inert stage for human activity. But human activity can now interact with nature in a destructive way to threaten human life, liberty and the pursuit of happiness.

We experience such destruction in the degradation of the Earth’s atmosphere, in rising sea levels, in the spread of infectious diseases, in the increasing pollution of land, sea and air, and in coastal floods and water shortages. The current US administration, I’d continue, is not only doing nothing to prevent this destruction, but also actively campaigning against people who are fighting it and trying to make the world safer.

Human freedom and independence require developing science to understand and cope with nature’s threats. When science is ignored, nature rules.

The administration claims that stopping these attempts increases the freedom of US citizens. It does not, however, and instead enslaves us to nature. Human freedom and independence require developing science to understand and cope with nature’s threats. When science is ignored, nature rules.

Yet the current US sovereign, a wannabe King, has made unprecedented attacks on science. His ignorance, denials and repudiations have unleashed untold damage and destruction to the health, welfare and safety of citizens. His actions threaten not only our lives but human lives elsewhere. His actions even threaten the global conditions that make human life possible at all.

Our grievances

My revised declaration would follow with a long and easily verifiable list of modern-day grievances. These would include the fact that Trump has declared that threats whose existence is scientifically well-established are hoaxes, scams and have “no basis in fact”. He has prevented agencies from investigating these threats and from developing technologies to use against them.

He has fired people who study these threats and installed political appointees to oversee funding of research. Despite publicly denying and ridiculing findings about climate change and rising seas, he has admitted their truth when it comes to protecting his own golf course.

The US administration has also declared, contrary to scientific findings, that claims of outbreaks of disease have been “fabricated” and that vaccines do not work. It has cancelled grants to develop vaccines, attacked vaccine makers, revoked recommendations that children be vaccinated, fired experts in vaccines, and damaged the process of vaccine development.

The US administration has sought to gut or close the most important US science agencies. He has withdrawn the US from international agencies that track and address the most important threats to human life and health. He has invented false facts about nature and forced US agencies to agree with him. And he has damaged and extorted America’s top universities by trying to dictate their research, hiring, admissions, courses and curricula.

The critical point

My document would reach a rousing conclusion.

A people, it would say, are only truly free and independent when they and their offspring are able to live in a safe environment, not stalked by disease, and educated freely without government interference. A sovereign who ignores and damages science is unfit to be a ruler by exposing the people to the enslavement of nature. Citizens in a democracy have the right to a leader who does not enslave them to nature.

The final sentence of the document would be: “Let us take those rights back.”

Like the Declaration of Independence 250 years ago, my imagined one may seem revolutionary but only expresses what Thomas Jefferson, the author of the original, called “the common sense of the subject.”

The post What a modern-day US Declaration of Independence should say appeared first on Physics World.

Alfred Tennyson was “the only poet since the time of Lucretius who has taken the trouble to understand the work and tendency of the men of science” said the English biologist Thomas Huxley on the occasion of Tennyson’s burial in the Poets’ Corner of Westminster Abbey on 12 October 1892. Tennyson’s acquaintance with science and its impact on his poetry is the subject of historian and broadcaster Richard Holmes’s new book The Boundless Deep: Young Tennyson, Science and the Crisis of Belief.

Born in 1809 – the same year as Charles Darwin – Tennyson matured at a time when science was transforming ideas about the universe. “It was stranger and vaster than previously thought,” writes Holmes, “and yet more vulnerable and paradoxically, more temporary. There were no Biblical eternities anymore.”

As a teenager Tennyson looked through telescopes and microscopes, and read books on physics, chemistry, botany and astronomy. In notebooks he interspersed poetic verses with careful observations of plants, birds, animals and other natural phenomena. In one poem he imagined himself on the Moon’s surface, in another as a microscopic creature. His verses expressed both wonder and suspicion. “O suns and spheres and stars … are you realities or semblances?” wrote the 14-year-old poet.

An unbreakable bond

While studying at the University of Cambridge, Tennyson met Arthur H Hallam and the two became inseparable, sharing interests in nature, poetry and science. In 1833 they spent a “science week” in London, visiting the new London Zoo in Regent’s Park, the Gallery of Practical Science in Piccadilly, and displays of magnets, microscopes and steam cannons.

That year several books on astronomy appeared, including one by Tennyson’s Cambridge tutor William Whewell, who coined the term “scientist”. The publications acquainted readers, including Tennyson and Hallam, with newly discovered star systems and “the nature of their formation, their growth over immense and previously inconceivable periods of time, and finally their slow but inevitable extinction”, as Holmes describes. “These ideas of so-called deep time and deep space were gradually transforming the whole notion of the material universe.”

That autumn, at age 22, Hallam unexpectedly died from a brain haemorrhage. It was the most traumatic event of Tennyson’s life, “a particular extinction from which he never recovered”, writes Holmes. Tennyson spent nearly two decades coping by writing In Memoriam A H H, published in 1850. In several sections near the poem’s midpoint, Tennyson seems to invoke nature as a possible source of solace in imagery that has challenged scholars ever since.

“Every evolutionist can cite the line,” wrote the evolutionary biologist Stephen J Gould in his 1995 book Dinosaur in a Haystack. “We would draw and quarter any imposter who couldn’t.” Gould was referring to the line “Nature red in tooth and claw”, a phrase from In Memoriam that many scholars think anticipates Darwinian evolution and consoled Tennyson. But Gould instead finds that the line only reflects the biological and geological catastrophism of Tennyson’s time and adds that Tennyson knew it held no comfort. “Science cannot tell us why a man should die so young,” Gould writes, “or how a grieving lover should resolve his suffering.”

Holmes gives a more nuanced interpretation, saying that Tennyson did not grieve and then seek solace in science. Rather, Tennyson’s grief began with his awareness that scientific truths prevented him from turning to religion; that the “death of an individual”, as Holmes writes, “counted for nothing within the vast and pitiless scale of geological death and extinction”. Tennyson’s grief sprang from his experience of a conflict between science and religion, which put him in a “state of hovering, or trembling, between science and religion, between empirical evidence and traditional faith”.

Life, poetry and science

Holmes has spent his career writing about Romantic poets and their world. For example, one of his previous books was The Age of Wonder: How the Romantic Generation Discovered the Beauty and Terror of Science. Holmes’s vast command of the era shows in his ability to identify the people from whom Tennyson learned what he knew.

He introduces us to Jane Marcet, an innovative scholar and writer whose books about physics and chemistry inspired not only Tennyson but also embarked the geologist Charles Lyell and physicist Michael Faraday on their scientific careers. Marcet would have been elected to the Royal Society, Holmes writes, “except for the slight hindrance that no female Fellow was admitted until 1921”. (Marcet’s husband, a Swiss doctor, made it in.) Meanwhile, the mathematician Mary Somerville – said to be “one of the only six persons in England who understands Laplace” – was a polymath whose books acquainted Tennyson with the entire spectrum of hard sciences.

Science, Holmes shows, is not a privileged knowledge that poets must bow before, nor a set of facts to accept or deny. Rather, its constant development reshapes our experience of the world as much as families and friendships, mentors and myths. The Boundless Deep is as instructive about the science found in Tennyson’s poetry as it is about science in human experience.

• 2025 William Collins 448 pp; £25.00 hb; £14.99 ebook

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Quantum mechanics is so full of strange phenomena that it’s not surprising that physicists have had to dream up some vivid metaphors to explain them. Who can’t help but think of cats in boxes when contemplating superposition or balls of jumbled yarn when musing over entanglement? Like all metaphors, these use familiar experiences to help understand the unfamiliar.

Metaphors come in many different types. “Love is a rose”, for instance, is a “filtrative” metaphor, in which a secondary subject (a rose) guides us how to perceive another, primary subject (love) by drawing our attention to key features.

In a “creative” metaphor, however, the secondary subject eventually becomes the technically correct term for the primary subject. This has happened over and over again in quantum mechanics: entanglement, superposition and spin are all examples.

A third kind is a “perceptual” metaphor, which seeks to recast our overall view of something. A good example is physician Lewis Thomas’s remark that the Earth is “most like a single cell.”

But one extraordinary metaphor proposed 10 years ago by Christopher Fuchs, a physicist at the University of Massachusetts Boston, involves a type of algae known as Euglena. Fuchs decided to invoke this single-celled, biological organism to help understand not just one quantum-mechanical phenomenon but possibly the deepest mystery of all: the relationship between quantum formalism and the world around us.

Subjective matters

Ever since Werner Heisenberg and others developed quantum mechanics more than a century ago, physicists have been debating what it means and what it says about the world. Over the years, there have been many different points of view, or “interpretations”, of quantum mechanics, but they all fall into two main camps.

One set claims that the formalism of quantum mechanics quantifies some actual, objective structure that existed even before humans and is independent of what we do. Another set of interpretations treats the formalism like a tool that lets humans make predictions about the world. In philosophical terms, the former interpretations are “ontological” and the latter “epistemological”.

Fuchs and a loose conglomerate of physicists and philosophers, however, have been advocating an entirely different approach, known as QBism. It says that any measurement we make – whether determining the spin of an electron or stamping our feet on the ground – is a new creation; it’s an experience that never existed in the world before. Quantum states aren’t therefore real states of affairs in nature but subjective probabilities we assign to our interactions with the world.

Subjective probabilities aren’t as strange as they sound, simply describing a user’s degree of belief about an individual event. Objective interpretations, in contrast, see probability distributions as physical. QBism’s conclusion that many pieces of the formalism are subjective simultaneously distances our subjective control over nature. For a one-horse race, I can predict the winner with certainty, but nevertheless, the race can still get washed out by rain. Even if I make a prediction with certainty about an event, nature can throw us a curveball and do otherwise.

For Fuchs and his supporters, quantum theory is therefore an appendix to Bayesian probability theory. Originally developed by the British philosopher and statistician Thomas Bayes in the 18th century, it evaluates a user’s judgment about how likely an outcome is (such as whether a horse will win a race) rather than being about pre-existing states of affairs (such as passively recording the speed of particles in a gas).

Fuchs calls his interpretation of quantum mechanics QBism as it derives from the term “Quantum Bayesianism”. Quantum mechanics, according to Fuchs, is a “user’s manual” that “anyone can pick up”, devised by experienced players to guide individual experimentalists to make wise bets on measurement outcomes.

Subjective interpretations of quantum mechanics treat the formalism as something for individuals to use and apply for all kinds of physical phenomena

The key point is that while quantum state assignments are subjective, the rules underlying them aren’t. They have been analysed, evaluated and corrected over time by communities of physicists. Subjective interpretations of quantum mechanics treat the formalism as something for individuals to use and apply for all kinds of physical phenomena.

Enter Euglena

If you’re struggling to get your head around all of this, that’s where Euglena comes in. It’s a single-celled freshwater algae, roughly 50 microns long, that has a long whip or “flagellum” that can sense nutrients and propel the organism towards the food. The tail, which is the product of many years of evolution, helps only the organism to which it is attached. However, by studying it, we can learn not just about an individual Euglena but also the wider environment in which it moves.

The metaphor of Euglena’s tail therefore does two things. First, it expresses the idea that quantum formalism is a manual – a means to get around in the world. Second, it says something about how we interact with the world.

Each organism uses its inherited tail, constantly tested and improved by a community of others, to “guess” how to get around in its environment. But each time the organism does, it encounters something in the environment it never did before.

Euglena’s tail can, in other words, help us to explain why quantum mechanics can be both a single-user theory and the product of extensive study. “By dissecting it,” Fuchs wrote in a 2016 arxiv preprint (1601.04360), “you can learn something about the world that all of us are immersed in.”

Like all metaphors, however, Euglena has its shortcomings.

Imagine standing above the Euglena and observing it through a microscope. It would be perfectly reasonable to say that “there is” an environment that the organism senses “thanks to” the whip. We might also conclude that what a Euglena encounters is objective, independent of its presence, and could be predicted by the organism, provided it had enough data and processing ability.

But all this assumes we are looking down from above to adopt a point of view completely detached from Euglena and its environment; we, as researchers, are outsiders. The Euglena organism itself is different. It has no such outside standpoint and each move is creative, encountering a fresh environment.

Physicists have no external standpoint from which to look down on the world

Now here’s the key point of the metaphor. Quantum physicists, too, cannot become “outsiders”. They have no external standpoint from which to look down on the world. They have the quantum formalism, but it’s a guide to what we find in our fresh encounters with the world.

The critical point

Fuchs’s Euglena metaphor has a much broader scope than the other scientific metaphors mentioned above. It is not so much about comparing a piece of the organism to quantum mechanics, but a way of comparing an organism’s adaptation to its world to the experimentalist’s user-manual; in turn, it becomes a story about what the world is.

The Euglena’s tiny whip is a way to grapple with the ontological lesson of quantum mechanics. You might, in fact, call it an “ontologizing” metaphor.

Robert P Crease  (click link below for full bio) is a professor in the Department of Philosophy, Stony Brook University, US, and Gino Elia is a philosopher of physics who is spending 2026–27 at the Ludwig Maximilian University of Munich, Germany, e-mail gino.elia@stonybrook.edu

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