The US dollar is the backbone of global trade and held by governments around the world as a safe haven in times of crisis.

It's so powerful that countries like Ecuador and Panama have adopted the dollar as their official currency, while Argentina for many years has tried to "dollarize" its economy.

But what happens if nations and private institutions were to lose trust in the dollar?

How did we get here? Well, after WWII the world order was re-established in part by tying the monetary systems to the value of the dollar, backed by gold. But since 1971 President Nixon cut that link to gold and the entire exchange system has since been tied directly to the dollar itself, its historic success and access to its financial markets.

That success gave America what was dubbed an "exorbitant privilege" to print money without fear of inflation and to build up national debt without consequence.

It also enables the US to flex its muscles on the international stage by imposing sanctions on countries and cutting off access to their all-important currency. That has led some countries, most notably China, to call for the dollar to be replaced as the world's reserve currency.

How difficult would it be to untangle the dollar from global trade, can any other nations offer the same conditions which has allowed the US currency to thrive, and what would happen if the dollar's role was replaced by newer digital currencies which operate outside traditional government control?

Presenter: Professor Ben Ansell

Contributors:

Material from:

Should we rethink who our city streets are for? It can often feel like there is a hierarchy on the roads, with cars needing to get from A to B as fast as they can, taking priority over people cycling or walking. But what if we flipped it on its head and put pedestrians at the top? Or, what if we saw our streets in a totally new light and instead decided they were places for meeting friends, playing or resting under a tree? Ben Ansell finds the people designing new streets, and he hears one radical idea that requires an entirely new language.

Ben visits a new kind of street where pedestrians have priority, not cars. It has been designed by traffic engineer Keith Firth at NRP. Campaigner Martin Cassini argues we could get rid of traffic lights to encourage drivers to pay better attention to pedestrians and to help ease traffic jams. But would all road users feel confident crossing without a dedicated beep or time to cross? Sohanna Srinivasan, head of Urban Planning Design at North Hertfordshire council, sets out her plan for how streets can have space built-in for people to fully enjoy their neighbourhoods while Dutch author Marco te Brömmelstroet says we need to rethink the language we use about cities. Change the language, change the mind set. Is it that simple?

Presenter: Ben Ansell

Have you ever wondered why some people age better than others?

We all know someone who looks great for their age, and is also in robust health. And yet someone else who is exactly the same age might look older, and may be living with an age-related illness.

Chronological age is not always be a good indicator of how well someone is maturing. So, if our skin - which is our largest organ - suggests how well, or badly, we're aging, then the state of our other organs and the systems that keep them running may also indicate how old we are.

This measure is called your biological age.

And there are many ways of measuring biological age, from the simple - the strength of your hand grip, to the detailed - looking at the changes in chemical markers attached to your DNA, called epigenetic markers.

They lie "on top of" the DNA, without changing it - much like an instruction written on a post-it note attached to a piece of sheet music. The instruction means the music can be expressed differently, without changing the tune. Epigenetics explains why the DNA in every one of our cells is the same, and yet the cells can look very different from one another. They can be heart cells, blood cells, hair cells and so on, because the markers cause different genes on the same DNA to be expressed.

Epigenetics has allowed scientists to create clocks to tell you your biological age: the latest one can even tell you how fast you're aging. Advances in epigenetics have led to the new science of cellular regeneration.

And the world's first clinical trials are underway in the USA for a treatment that transforms old, dysfunctional and damaged cells into young healthy ones - treating aging itself.

Presenter: Ben Ansell

Contributors:

Of the 195 widely-recognized sovereign countries in the world, only a quarter are monarchies.

And of those 43 monarchies, 15 of those have the same King. That’s Charles III, who’s head of state for Commonwealth territories as large as Australia and Canada, and as far apart as the UK and Tuvalu in the South Pacific.

In the other 28, the ruling monarchs can be called Kings, Emirs, Sultans, and there’s an Emperor on the Chrysanthemum throne in Japan.

Of course, there are also Queens - but some modern monarchies such as Japan and Lichtenstein still don’t allow female succession. In others, eldest daughters are passed over for their younger brothers - and this still happens in Spain and Monaco.

If this all seems a bit medieval, that's because it is! Monarchy is a system of governance that developed hundreds - or in the case of Japan - more than 1000 years ago, so it can look outdated through a 21st century lens.

But it's enduring, and opinion polls suggest it can be popular. So what does monarchy mean in the modern age? Which royal families are not only surviving, but are expanding their spheres of power and influence, and why the newest "monarchies" in the USA, Russia and China are not even royal at all.

Presenter: Professor Ben Ansell

Contributors:

As generative AI and Deepfake technology has progressed over the last decade, you could be forgiven for thinking that it's never been more difficult to try to work out what is authentic and what is fake.

The search for authenticity is not new. It's a task that's challenged humanity for hundreds of years. Forgers have always tried to pass off copies as great artworks, but it's not always clear when an artist was responsible for an entire painting or farmed out parts of the job to apprentices. A few well-known modern artists outsource all of the construction and manufacture of some of their works to skilled craftsmen and women.

Although the idea is theirs, does that make the final product somehow less than the genuine article?

Idiosyncrasies, perceived flaws or personal flourishes are often key indicators that show an image is authentic. We use those same tell-tale signs to judge the authenticity of another type of image: the one that politicians want to portray.

How important is it to be a politician who is seen as authentic by voters? How can we measure political authenticity? If someone is carefully crafting their image on social media, how real is it? And even if it is fake, do voters care, if they have been seduced by the illusion?

Presenter: Ben Ansell

Contributors:

Rethink is a BBC co-production with the Open University.

In 2023, ChatGPT took Artificial Intelligence into the mainstream. Now there's a bewildering choice of human-like chatbots to choose from. Generative AIs can produce pictures and video from a text prompt, and many websites and apps are now labelled "Powered by AI".

This new technology can do lots of things and tech companies have raised vast amounts of money from investors based on its potential.

But what is AI actually for?

Certain specialised AIs have a clear purpose. AlphaFold2 can predict how proteins fold-up and won its creators the Nobel Prize for Chemistry, and Google Translate is an AI with a purpose that’s clear from its name.

But so far there is no must-have or "killer" application for the Large Language Models and Generative AIs.

The future of AI is equally hazy. Will AI somehow lead to all-purpose "Artificial General Intelligence", autonomous robots or even machine consciousness? Or is this all just the stuff of fantasy and nightmares?

Presenter: Ben Ansell

Contributors:

Rethink is a BBC co-production with the Open University.

The government has launched the Pride in Place scheme but is it possible to regenerate urban areas without leaving local people out?

Most buildings have a certain shelf life before they need renovating. Social norms change and the ways people interact develop as society transforms with time. And local economies can change dramatically with once prosperous industrial areas falling silent, or tourist hot spots left behind by low-cost air travel.

Presenter: Ben Ansell

Contributors:

Rethink is a BBC co-production with the Open University.

People are living longer and delaying life's milestone moments. How does this affect our middle years and should we be paying more attention to people in this phase of their lives?

For some, middle age can be a very challenging period in their lives. Today, people are postponing the milestones in life that traditionally signified a change in priorities. People are having children later in life meaning parents in their 40s or even 50s are looking after small children. Jobs for life no longer exist and housing is so expensive that many have no choice but to pay costly rents.

Presenter: Ben Ansell

Contributors:

Ben Akers - Co-founder and co-CEO of Talk Club

Rethink is a BBC co-production with the Open University.

The Night Times Industries Association says one in four venues have shut down since 2020, and the sector will face an irreversible decline unless the government provides urgent support.

The industry was one of the worst hit during the pandemic, and it's asking for cuts to National Insurance, a permanent cut in VAT and a reform of business rates to help it keep afloat.

The NTIA claims the night time economy contributes more than £153 billion to the UK economy and supports over 2 million jobs.

Culturally, the sector punches above its weight. The nightclub boom in the last 50 years gave us disco, acid house, drum and bass and grime, as well as many other sub-genres of music. But nightclubs are expensive and consumers are finding their thrills elsewhere; drink is cheaper from supermarkets, and why search for someone you fancy on the dancefloor when you can use a dating app?

And as nightclubs struggle, so do small music venues, where artists like Ed Sheeran, Dua Lipa, Coldplay, Arctic Monkeys Blur and Oasis started out, as well as many others.

People are willing to pay hundreds of pounds to see those same artists in giant venues like Co-op Live in Manchester or at Wembley Stadium, so what can be done to make sure the next wave of new artists have somewhere to play? Should the government intervene? Should big venues subsidise smaller ones, or is it up to fans to throw them a lifeline?

Or has nightlife in its current form - much like variety music halls - taken its last curtain call?

Presenter: Ben Ansell

Contributors:

Michael Kill - CEO, Night Time Industries Association

Do you agree with either of these statements?

Illegal migrants come here and are a burden on services and the taxpayer.

They may seem on opposite poles of the political spectrum, but both anti-migrant campaigners and anti-capitalists share an identical mindset. Both are demonstrating zero-sum thinking; the belief that if one group wins, another has to lose.

In itself, zero-sum thinking isn't moral or immoral, right or wrong. But Economists claim it leads to poor economic policy, and they say evidence shows it is possible to create win-win situations for everyone.

But many of the main parties at Westminster also use zero-sum thinking in their political rhetoric - from Reform and the Greens, to the Conservatives and Labour. Also, the first past the post electoral system is literally a zero-sum process. So is this kind of thinking baked-into UK politics?

So are there particular groups of people that are more prone to zero-sum beliefs? Where did this mindset come from? What economic conditions encourage zero-sum thinking, and how deeply are these beliefs held?

Presenter: Ben Ansell

Contributors: